Event Hooks
Noora has four hook systems that run custom code at key lifecycle points:
| System | Registered via | Runs in | Use case |
|---|---|---|---|
| Gateway hooks | HOOK.yaml + handler.py in ~/.noora/hooks/ | Gateway only | Logging, alerts, webhooks |
| Plugin hooks | ctx.register_hook() in a plugin | CLI + Gateway | Tool interception, metrics, guardrails |
| Shell hooks | hooks: block in ~/.noora/config.yaml pointing at shell scripts | CLI + Gateway | Drop-in scripts for blocking, auto-formatting, context injection |
| Outbound webhooks | hooks.outbound: list in ~/.noora/config.yaml | CLI + Gateway | Push signed lifecycle events to external HTTP endpoints — CI, dashboards, other agents |
Hook callback errors are isolated and logged rather than crashing the agent. Hooks are not all passive: directive/control hooks can change flow, transforms can replace content, and a shell pre_tool_call hook can block or fail closed.
Gateway Event Hooks
Gateway hooks fire automatically during gateway operation (Telegram, Discord, Slack, WhatsApp, Teams) without blocking the main agent pipeline.
Creating a Hook
Each hook is a directory under ~/.noora/hooks/ containing two files:
~/.noora/hooks/
└── my-hook/
├── HOOK.yaml # Declares which events to listen for
└── handler.py # Python handler function
HOOK.yaml
name: my-hook
description: Log all agent activity to a file
events:
- agent:start
- agent:end
- agent:step
The events list determines which events trigger your handler. You can subscribe to any combination of events, including wildcards like command:*.
handler.py
import json
from datetime import datetime
from pathlib import Path
LOG_FILE = Path.home() / ".noora" / "hooks" / "my-hook" / "activity.log"
async def handle(event_type: str, context: dict):
"""Called for each subscribed event. Must be named 'handle'."""
entry = {
"timestamp": datetime.now().isoformat(),
"event": event_type,
**context,
}
with open(LOG_FILE, "a") as f:
f.write(json.dumps(entry) + "\n")
Handler rules:
- Must be named
handle - Receives
event_type(string) andcontext(dict) - Can be
async defor regulardef— both work - Errors are caught and logged, never crashing the agent
Available Events
| Event | When it fires | Context keys |
|---|---|---|
gateway:startup | Gateway process starts | platforms (list of active platform names) |
session:start | New messaging session created | platform, user_id, session_id, session_key |
session:end | Session ended (before reset) | platform, user_id, session_key |
session:reset | User ran /new or /reset | platform, user_id, session_key |
session:compress | Context compression completed for a session | platform, session_id, old_session_id (empty when compacted in place), in_place (bool — true = transcript compacted on the same id, false = rotated from old_session_id), compression_count |
agent:start | Agent begins processing a message | platform, user_id, chat_id, thread_id (forum-topic / thread root id; empty when not in a thread), chat_type ("dm" | "group" | "forum"; empty if unknown), session_id, message (truncated to 500 chars) |
agent:step | Each iteration of the tool-calling loop | platform, user_id, session_id, iteration, tool_names |
agent:end | Agent finishes processing | same keys as agent:start, plus response (truncated to 500 chars) |
reaction:added | An emoji reaction was added to a message the bot can see (Slack adapter currently). Requires the reactions:read scope + the reaction_added bot event subscription; the bot must be a member of the channel. | platform, reaction, user_id, item_user_id, item_type, channel_id, message_ts, team_id, event_ts, raw_event |
reaction:removed | An emoji reaction was removed from a message the bot can see. Requires the reaction_removed bot event subscription. | same shape as reaction:added |
command:* | Any slash command executed | platform, user_id, command, args |
Wildcard Matching
Handlers registered for command:* fire for any command: event (command:model, command:reset, etc.). Monitor all slash commands with a single subscription.
A handler posting a follow-up message into the same Telegram forum topic should include message_thread_id=int(thread_id) when chat_type == "forum" and thread_id is non-empty.
Examples
Telegram Alert on Long Tasks
Send yourself a message when the agent takes more than 10 steps:
# ~/.noora/hooks/long-task-alert/HOOK.yaml
name: long-task-alert
description: Alert when agent is taking many steps
events:
- agent:step
# ~/.noora/hooks/long-task-alert/handler.py
import os
import httpx
THRESHOLD = 10
BOT_TOKEN = os.getenv("TELEGRAM_BOT_TOKEN")
CHAT_ID = os.getenv("TELEGRAM_HOME_CHANNEL")
async def handle(event_type: str, context: dict):
iteration = context.get("iteration", 0)
if iteration == THRESHOLD and BOT_TOKEN and CHAT_ID:
tools = ", ".join(context.get("tool_names", []))
text = f"⚠️ Agent has been running for {iteration} steps. Last tools: {tools}"
async with httpx.AsyncClient() as client:
await client.post(
f"https://api.telegram.org/bot{BOT_TOKEN}/sendMessage",
json={"chat_id": CHAT_ID, "text": text},
)
Command Usage Logger
Track which slash commands are used:
# ~/.noora/hooks/command-logger/HOOK.yaml
name: command-logger
description: Log slash command usage
events:
- command:*
# ~/.noora/hooks/command-logger/handler.py
import json
from datetime import datetime
from pathlib import Path
LOG = Path.home() / ".noora" / "logs" / "command_usage.jsonl"
def handle(event_type: str, context: dict):
LOG.parent.mkdir(parents=True, exist_ok=True)
entry = {
"ts": datetime.now().isoformat(),
"command": context.get("command"),
"args": context.get("args"),
"platform": context.get("platform"),
"user": context.get("user_id"),
}
with open(LOG, "a") as f:
f.write(json.dumps(entry) + "\n")
Session Start Webhook
POST to an external service on new sessions:
# ~/.noora/hooks/session-webhook/HOOK.yaml
name: session-webhook
description: Notify external service on new sessions
events:
- session:start
- session:reset
# ~/.noora/hooks/session-webhook/handler.py
import httpx
WEBHOOK_URL = "https://your-service.example.com/noora-events"
async def handle(event_type: str, context: dict):
async with httpx.AsyncClient() as client:
await client.post(WEBHOOK_URL, json={
"event": event_type,
**context,
}, timeout=5)
Tutorial: BOOT.md — Run a Startup Checklist on Every Gateway Boot
A popular pattern from the community: drop a Markdown checklist at ~/.noora/BOOT.md, and have the agent run it once every time the gateway starts. Useful for "on every boot, check overnight cron failures and ping me on Discord if anything failed," or "summarize the last 24h of deploy.log and post it to Slack #ops."
This tutorial shows how to build it yourself as a user-defined hook. Noora does not ship a built-in BOOT.md hook — you wire up exactly the behavior you want.
What we're building
- A file at
~/.noora/BOOT.mdwith natural-language startup instructions. - A gateway hook that fires on
gateway:startup, spawns a one-shot agent with your gateway's resolved model/credentials, and runs the BOOT.md instructions. - A
[SILENT]convention so the agent can opt out of sending a message when there's nothing to report.
Step 1: Write your checklist
Create ~/.noora/BOOT.md. Write it as if you were giving instructions to a human assistant:
# Startup Checklist
1. Run `noora cron list` and check if any scheduled jobs failed overnight.
2. If any failed, summarize them for Discord #ops (the hook delivers your final response to its configured target).
3. Check if `/opt/app/deploy.log` has any ERROR lines from the last 24 hours. If yes, summarize them and include in the same report.
4. If nothing went wrong, reply with only `[SILENT]` so no message is sent.
The agent sees this as part of its prompt, so anything you can describe in plain language works — tool calls, shell commands, sending messages, summarizing files.
Step 2: Create the hook
~/.noora/hooks/boot-md/
├── HOOK.yaml
└── handler.py
~/.noora/hooks/boot-md/HOOK.yaml
name: boot-md
description: Run ~/.noora/BOOT.md on gateway startup
events:
- gateway:startup
~/.noora/hooks/boot-md/handler.py
"""Run ~/.noora/BOOT.md on every gateway startup."""
import logging
import threading
from pathlib import Path
logger = logging.getLogger("hooks.boot-md")
BOOT_FILE = Path.home() / ".noora" / "BOOT.md"
def _build_prompt(content: str) -> str:
return (
"You are running a startup boot checklist. Follow the instructions "
"below exactly.\n\n"
"---\n"
f"{content}\n"
"---\n\n"
"Execute each instruction. Put any user-facing summary in your "
"final response — the hook delivers it to the configured channel "
"(e.g. Discord or Slack); you do not send messages yourself.\n"
"If nothing needs attention and there is nothing to report, reply "
"with ONLY: [SILENT]"
)
def _run_boot_agent(content: str) -> None:
"""Spawn a one-shot agent and execute the checklist.
Uses the gateway's resolved model and runtime credentials so this works
against custom endpoints, aggregators, and OAuth-based providers alike.
"""
try:
from gateway.run import _resolve_gateway_model, _resolve_runtime_agent_kwargs
from run_agent import AIAgent
agent = AIAgent(
model=_resolve_gateway_model(),
**_resolve_runtime_agent_kwargs(),
platform="gateway",
quiet_mode=True,
skip_context_files=True,
skip_memory=True,
max_iterations=20,
)
result = agent.run_conversation(_build_prompt(content))
response = (result.get("final_response", "") or "").strip()
if response.upper() not in {"[SILENT]", "SILENT", "NO_REPLY", "NO REPLY"}:
logger.info("boot-md completed: %s", response[:200])
else:
logger.info("boot-md completed (nothing to report)")
except Exception as e:
logger.error("boot-md agent failed: %s", e)
async def handle(event_type: str, context: dict) -> None:
if not BOOT_FILE.exists():
return
content = BOOT_FILE.read_text(encoding="utf-8").strip()
if not content:
return
logger.info("Running BOOT.md (%d chars)", len(content))
# Background thread so gateway startup isn't blocked on a full agent turn.
thread = threading.Thread(
target=_run_boot_agent,
args=(content,),
name="boot-md",
daemon=True,
)
thread.start()
The two key lines:
_resolve_gateway_model()reads the gateway's currently-configured model._resolve_runtime_agent_kwargs()resolves provider credentials the same way a normal gateway turn does — including API keys, base URLs, OAuth tokens, and credential pools.
Without these, a bare AIAgent() falls back to built-in defaults and will 401 against any non-default endpoint.
Step 3: Test it
Restart the gateway:
noora gateway restart
Watch the logs:
noora logs --follow --level INFO | grep boot-md
You should see Running BOOT.md (N chars) followed by either boot-md completed: ... (summary of what the agent did) or boot-md completed (nothing to report) when the agent replied with an exact silence token such as [SILENT].
Delete ~/.noora/BOOT.md to disable the checklist — the hook stays loaded but silently skips when the file isn't there.
Extending the pattern
- Schedule-aware checklists: key off
datetime.now().weekday()inside BOOT.md's instructions ("if it's Monday, also check the weekly deploy log"). The instructions are free-form text, so anything the agent can reason about is fair game. - Multiple checklists: point the hook at a different file (
STARTUP.md,MORNING.md, etc.) and register separate hook directories for each. - Non-agent variant: if you don't need a full agent loop, skip
AIAgententirely and have the handler post a fixed notification directly viahttpx. Cheaper, faster, and has no provider dependency.
Why this isn't a built-in
An earlier version of Noora shipped this as a built-in hook and silently spawned an agent with bare defaults on every gateway boot. That surprised users with custom endpoints and made the feature invisible to users who didn't know it was running. Keeping it as a documented pattern — built by you, in your hooks directory — means you see exactly what it does and opt in by writing the files.
How It Works
- On gateway startup,
HookRegistry.discover_and_load()scans~/.noora/hooks/ - Each subdirectory with
HOOK.yaml+handler.pyis loaded dynamically - Handlers are registered for their declared events
- At each lifecycle point,
hooks.emit()fires all matching handlers - Errors in any handler are caught and logged — a broken hook never crashes the agent
Gateway hooks only fire in the gateway (Telegram, Discord, Slack, WhatsApp, Teams). The CLI does not load gateway hooks. For hooks that work everywhere, use plugin hooks.
Plugin Hooks
Plugins can register hooks that fire in both CLI and gateway sessions. These are registered programmatically via ctx.register_hook() in your plugin's register() function.
For plugin packaging and registration details, see the Plugins guide.
def register(ctx):
ctx.register_hook("pre_tool_call", my_tool_observer)
ctx.register_hook("post_tool_call", my_tool_logger)
ctx.register_hook("pre_llm_call", my_memory_callback)
ctx.register_hook("post_llm_call", my_sync_callback)
ctx.register_hook("on_session_start", my_init_callback)
ctx.register_hook("on_session_end", my_cleanup_callback)
# Kanban board lifecycle (dependency-wait blocking may fire inside its transaction):
ctx.register_hook("kanban_task_claimed", my_claim_callback) # dispatcher process
ctx.register_hook("kanban_task_completed", my_done_callback) # worker process
ctx.register_hook("kanban_task_blocked", my_blocked_callback) # worker process
General rules for all hooks:
- Callbacks receive keyword arguments. Always accept
**kwargsfor forward compatibility. - Callback exceptions are logged and skipped; later callbacks continue.
- The catalog below is descriptive: observers ignore returns, transforms accept the first valid string replacement, and directive/control hooks consume documented return shapes. Plugin middleware is a separate registry and surface, not another hook category.
- Correlation fields such as
turn_id,api_request_id,task_id,session_id, andapi_call_countare hook-specific and may be absent. Treat IDs as opaque. - Runtime event-name validity comes from
noora_cli.plugins.VALID_HOOKS.noora hooks listlists configured shell/outbound hooks, not every available event;noora hooks test <event>reports the valid set only when an invalid event is supplied.
Cache-safe system prompt sections
Plugins that need durable, always-on guidance can register a bounded system
prompt section instead of injecting the same text through pre_llm_call on
every turn:
def board_rules(session_info):
return f"Apply the worker rules for profile {session_info['profile_name']}."
def register(ctx):
ctx.register_system_prompt_section(
"kanban-advanced.worker-rules",
board_rules, # a string is also accepted
position="after_memory",
max_chars=4000,
)
The contract is deliberately narrow:
- IDs are global, stable, 1–128 character lowercase identifiers using only
letters, numbers,
.,_, and-. Duplicate IDs are rejected. after_memoryis the only placement anchor. Sections are sorted by ID, rendered after memory/profile context and before session metadata; plugins cannot reorder or replace core prompt content.- A callable receives a read-only mapping with
session_id,model,provider,platform,profile_name, andcwd. It runs once for a new session. Its rendered bytes are frozen on compression and recovered from the already-persisted full system prompt after a process restart/resume; plugin state is not re-read for an existing session. max_charsis capped at 4,000 characters. All plugin sections together, including their audit headings, are capped at 8,000 characters and 32 sections. Empty, non-string, oversized, aggregate-over-budget, or raising sections are skipped with a warning; prompt construction continues.- Every accepted section is named in the prompt and logged at session start with its plugin, position, and character count.
Use pre_llm_call for truly dynamic per-turn context. There is intentionally
no plugin environment-hints hook in this contract: changing cwd, branch, or
other environment data must not silently mutate a session's cached prompt.
Such a hook needs a concrete consumer and the same frozen/resume-safe semantics
before it can be added.
Shipped plugin-hook catalog
Payload fields below are the exact event-specific fields supplied by each call site. For backward compatibility, PluginManager also adds telemetry_schema_version="noora.observer.v1" to every plugin-hook callback. That legacy envelope marker does not mean all hook payloads share one semantic schema; new versioned contracts belong to their concrete event or capability family.
| Hook | Category | Exact timing and return behavior | Explicit payload fields | Privacy / sensitivity |
|---|---|---|---|---|
pre_tool_call | Directive/control | Once before execution; first valid block or approve directive wins, and modify returns are shallow-merged into the tool arguments. | tool_name, args, task_id, session_id, tool_call_id, turn_id, api_request_id, middleware_trace | Raw arguments may contain user content, paths, commands, or secrets. |
post_tool_call | Observer | After blocked, error, or successful result; return ignored. | tool_name, args, result, task_id, session_id, tool_call_id, turn_id, api_request_id, duration_ms, status, error_type, error_message, middleware_trace | Result/error text may contain arbitrary tool or user content and secrets. |
transform_tool_result | Transform | After post_tool_call, before conversation append; first string replaces the result. | tool_name, args, result, task_id, session_id, tool_call_id, turn_id, api_request_id, duration_ms, status, error_type, error_message | Exposes the full model-bound result and arguments. |
transform_terminal_output | Transform | After bounded foreground process capture, before final output limiting; first string replaces output. | command, output, returncode, task_id, env_type | Command/output may contain credentials. |
pre_transcription | Transform | Fired by the STT dispatcher after provider resolution and before any backend (built-in, command-type, or plugin-registered) is invoked; dict results are applied in registration order, last-writer-wins per field (prompt, language, model; file_path is read-only). | file_path, provider, model, language, prompt, source | The final prompt is uploaded to the configured STT provider with the audio — keep secrets out of hook returns. |
pre_llm_call | Directive/control | Once per turn before the loop; all valid string/{"context": ...} returns are joined and injected into the user message. | session_id, task_id, turn_id, user_message, conversation_history, is_first_turn, model, platform, parent_session_id, sender_id | Full user message and conversation history. |
post_llm_call | Observer | Successful, non-interrupted turn finalization; return ignored. | session_id, task_id, turn_id, user_message, assistant_response, conversation_history, model, platform | Full prompt, response, and history. |
transform_llm_output | Transform | Before post_llm_call and final delivery; first non-empty string replaces the response. | response_text, session_id, model, platform | Full final assistant text. |
pre_verify | Directive/control | At the bounded edited-code verify gate; first valid continue/block-stop directive keeps the turn going. | session_id, platform, model, coding, attempt, final_response, changed_paths | Draft response and changed paths. |
pre_api_request | Observer | Per provider attempt, immediately before the request; return ignored. | task_id, turn_id, api_request_id, session_id, user_message, conversation_history, platform, model, provider, base_url, api_mode, api_call_count, retry_count, request_messages, message_count, tool_count, approx_input_tokens, request_char_count, max_tokens, started_at, middleware_trace, request | High sensitivity: legacy user_message, conversation_history, and request_messages are intentionally raw; prefer sanitized request. |
post_api_request | Observer | After normalized provider success; return ignored. | task_id, turn_id, api_request_id, session_id, platform, model, provider, base_url, api_mode, api_call_count, api_duration, started_at, ended_at, finish_reason, message_count, response_model, response, usage, assistant_message, assistant_content_chars, assistant_tool_call_count | Sanitized response is available, but raw normalized assistant_message may contain model/user content; usage is accounting data. |
api_request_error | Observer | On each failed provider attempt; return ignored. | task_id, turn_id, api_request_id, session_id, platform, model, provider, base_url, api_mode, api_call_count, api_duration, started_at, ended_at, status_code, retry_count, max_retries, retryable, reason, error, request | Error text may contain provider/user data; request is intended to be sanitized. |
on_stream_start | Observer | Dispatched when a streaming LLM response begins; delivered off the token path via a host-owned bounded queue with one worker per callback; return ignored. | turn_id, iteration, session_id, model, provider, surface | Identifiers and routing metadata only. |
on_stream_delta | Observer | Dispatched per normalized streaming text delta via the bounded observer queue; a stalled callback drops only its own oldest events; return ignored. | delta, kind (text or reasoning), turn_id, iteration, session_id, model, provider, surface | Delta text is raw model output; reasoning deltas require the plugins.stream_reasoning_deltas opt-in. |
on_stream_end | Observer | Dispatched when a streaming response finishes or errors, after the stream closes; return ignored. | final_text, finished, error, turn_id, iteration, session_id, model, provider, surface | Full assembled response text; error text may include provider data. |
on_interim_message | Observer | Dispatched when a mid-loop assistant message is surfaced before the final answer (streaming or non-streaming); return ignored. | text, already_streamed, turn_id, iteration, session_id, model, provider, surface | Full interim assistant text. |
transform_api_error_classification | Transform | On each failed provider attempt, at the top of the built-in classifier; all callbacks run, then the first dict with a valid reason wins (run-all-then-pick-first), and skipped valid results log a runtime warning. Python plugins only. | provider, model, status_code, error_type, error_code, error_message, error_body, error, approx_tokens, context_length, num_messages | error_message and error_body may contain raw provider/user data. |
on_session_start | Observer | First turn of a new session; return ignored. | session_id, model, platform | Identifiers and routing metadata only. |
on_session_end | Observer | Canonically at each turn finalization; CLI/TUI exits have additional reduced legacy shapes. Return ignored. | Canonical: session_id, task_id, turn_id, completed, failed, interrupted, turn_exit_reason, model, platform; exit paths may add reason/api_request_id and omit fields. | IDs, model/platform, and outcome; canonical payload has no message body. |
on_session_finalize | Observer | CLI/TUI/gateway teardown through finalize_session; gateway shutdown or expiry may finalize without a reset. Return ignored. | Surface-dependent session_id, platform, optionally reason, old_session_id, new_session_id | Session and routing identifiers. |
on_session_reset | Observer | CLI/TUI session boundary and gateway after the replacement session exists; return ignored. | CLI: session_id, platform, reason; TUI: session_id, platform; gateway: those plus reason, old_session_id, new_session_id | Session and routing identifiers. |
on_skill_lifecycle | Observer | After an authoritative skill-usage state change; return ignored. | action, skill_name, provenance, task_id, session_id, use_count, reused, reuse_after_patch | Exposes the local skill name and provenance. |
subagent_start | Observer | Child constructed and about to run; return ignored. | parent_session_id, parent_turn_id, parent_subagent_id, child_session_id, child_subagent_id, child_role, child_goal | Child goal may contain user/project content. |
subagent_stop | Observer | Child exit; return ignored. | parent_session_id, parent_turn_id, child_session_id, child_role, child_summary, child_status, tool_call_history, duration_ms | Summary and redacted tool-history metadata may reveal project structure. |
pre_gateway_dispatch | Directive/control | Incoming non-internal message before auth/pairing/dispatch; first valid skip, rewrite, or allow controls flow. | event, gateway, session_store | Extremely privileged in-process objects expose inbound user/routing data and host handles. |
gateway_platform_event | Observer | After the gateway's profile-scoped authorization succeeds, when a supported platform-native event is normalized at the gateway boundary (Telegram: reactions, message edits; Discord: message edits/deletes, thread created/renamed); return ignored. | platform, event_type, payload (event-type-specific dict — see the per-event contracts below) | Normalized plain-dict envelope only; raw SDK objects, adapter handles, and bot clients are never exposed. |
pre_command | Observer | Recognized slash command about to be dispatched, before the handler runs, on CLI and gateway cold-path dispatch; return ignored in v1 (directive-shaped dicts are logged at debug). Gateway running-agent intercept commands (/stop, /approve during an active run) are deliberately excluded — control-plane escape hatches must stay outside plugin reach. | surface ("cli" | "gateway"), command (canonical name), alias_used, args_raw, session_key, platform | args_raw may contain user content or secrets typed after the command. |
pre_approval_request | Observer | Before prompted or smart approval; return ignored. | command, description, pattern_key, pattern_keys, session_key, surface, turn_id, tool_call_id | Command may contain secrets; smart observer preparation force-redacts, but surfaces do not all have identical redaction. |
post_approval_response | Observer | After a decision, timeout, or gateway notification failure; return ignored. | command, description, pattern_key, pattern_keys, session_key, surface, turn_id, tool_call_id, choice; smart path may add decided_by | Same command sensitivity plus decision metadata. |
kanban_task_claimed | Observer | After claim commit, in dispatcher process before worker spawn; return ignored. | task_id, profile_name, board, assignee, run_id | Board/task/profile/assignee identifiers. |
kanban_task_completed | Observer | After completion and cleanup, usually in worker process; return ignored. | task_id, profile_name, board, assignee, run_id, summary | Summary may contain project/user content. |
kanban_task_blocked | Observer | After a blocked transition; the dependency-wait path fires before its transaction exits. Return ignored. | task_id, profile_name, board, assignee, run_id, reason | Reason may contain project/user content. |
on_kanban_worker_spawned | Observer | After spawn_fn returns and the worker PID is persisted; runs inside the dispatch lock, keep callbacks fast. Return ignored. | task_id, profile_name, board, assignee, run_id, worker_pid, workspace_path | workspace_path is a filesystem path and may reveal project layout or usernames. |
on_kanban_worker_exited | Observer | Tick-derived: after detect_crashed_workers reclaims a dead-PID task and the reclaim commits. Return ignored. | task_id, profile_name, board, assignee, run_id, worker_pid, exit_kind, exit_code, outcome, retry_status | Identifiers and exit metadata only. |
on_kanban_worker_stale_claim | Observer | After a TTL-expired claim is reclaimed; live-PID extensions don't fire. Return ignored. | task_id, profile_name, board, assignee, run_id, worker_pid, heartbeat_stale, retry_status | Identifiers and claim metadata only. |
on_kanban_task_updated | Observer | After a committed task-field write outside the claim/complete/block lifecycle (assign, overrides, dashboard editors). Return ignored. | task_id, profile_name, board, assignee, run_id, changed_fields | changed_fields carries field names only, never values; the named title/body values in the board DB may contain user/project content. |
on_kanban_dispatch_tick | Observer | Once per dispatcher tick, strictly after the dispatch lock is released; idle and contended ticks fire too. Return ignored. | board, profile_name, dry_run, outcome, result | result is the tick's DispatchResult and carries task ids, assignees, and workspace paths. |
Streaming output hooks
These observer-only hooks let plugins consume streaming LLM output for telemetry, live dashboards, or TTS pipelines without changing the response. They are delivered through host-owned bounded queues with one background worker per registered callback, so plugin callbacks never run inline on the token path. If one callback stalls, only that callback's queue can fill and drop its oldest pending observer event; other observers continue receiving events independently.
Register them like any other plugin hook:
def on_delta(delta, kind, model, provider, **kwargs):
if kind == "text":
print(delta, end="", flush=True)
def register(ctx):
ctx.register_hook("on_stream_delta", on_delta)
Common fields for all four hooks:
| Parameter | Type | Description |
|---|---|---|
turn_id | str | Opaque turn identifier, when available |
iteration | int | Current API-call/tool-loop iteration |
session_id | str | Current Noora session id |
model | str | Active model identifier |
provider | str | Active provider name |
surface | str | Calling surface, e.g. cli, discord, telegram |
Additional fields:
| Hook | Extra fields |
|---|---|
on_stream_start | none |
on_stream_delta | delta: str, `kind: "text" |
on_stream_end | final_text: str, finished: bool, `error: str |
on_interim_message | text: str, already_streamed: bool |
on_interim_message can also fire after a non-streaming response, so registering only that hook does not force a provider call onto streaming transport.
Reasoning deltas are not exposed to plugins by default. Opt in explicitly:
plugins:
stream_reasoning_deltas: true
Return values are ignored. To keep the stream fast, callbacks should enqueue their own work and return quickly. Exceptions are logged and do not stop the stream.
pre_tool_call
Fires immediately before every tool execution — built-in tools and plugin tools alike.
Callback signature:
def my_callback(tool_name: str, args: dict, task_id: str, **kwargs):
| Parameter | Type | Description |
|---|---|---|
tool_name | str | Name of the tool about to execute (e.g. "terminal", "web_search", "read_file") |
args | dict | The arguments the model passed to the tool |
task_id | str | Session/task identifier. Empty string if not set. |
Fires: In model_tools.py, inside handle_function_call(), before the tool's handler runs. Fires once per tool call — if the model calls 3 tools in parallel, this fires 3 times.
Return value — block or require approval:
return {"action": "block", "message": "Reason the tool call was blocked"}
# or
return {"action": "approve", "message": "Why approval is required", "rule_key": "optional:scope"}
The first valid directive wins (Python plugins registered first, then shell hooks). block requires a non-empty message and short-circuits the tool with that text as the error returned to the model. approve escalates the call to the existing human-approval gate; message and rule_key are optional, and denial, timeout, or gate error fails closed. Other return values are ignored, so existing observer-only callbacks keep working unchanged.
Return value — rewrite the tool's arguments:
return {"action": "modify", "args": {"new_string": "fixed content"}}
The returned args dictionary is shallow-merged over the original tool arguments before the tool executes. Multiple modify hooks accumulate — each hook's keys are merged into one accumulated dict built from the original args, so hook A changing path and hook B changing content both survive. If two hooks modify the same key, the later hook wins.
Shell hooks also accept the Claude Code-compatible format:
{"decision": "modify", "tool_input": {"new_string": "fixed content"}}
Both formats are normalized internally to {"action": "modify", "args": {...}}.
Use cases: Logging, audit trails, tool call counters, blocking dangerous operations, rate limiting, per-user policy enforcement, argument sanitization, path rewriting, injecting default parameters.
Example — tool call audit log:
import json, logging
from datetime import datetime
logger = logging.getLogger(__name__)
def audit_tool_call(tool_name, args, task_id, **kwargs):
logger.info("TOOL_CALL session=%s tool=%s args=%s",
task_id, tool_name, json.dumps(args)[:200])
def register(ctx):
ctx.register_hook("pre_tool_call", audit_tool_call)
Example — warn on dangerous tools:
DANGEROUS = {"terminal", "write_file", "patch"}
def warn_dangerous(tool_name, **kwargs):
if tool_name in DANGEROUS:
print(f"⚠ Executing potentially dangerous tool: {tool_name}")
def register(ctx):
ctx.register_hook("pre_tool_call", warn_dangerous)
post_tool_call
Fires immediately after every tool execution returns.
Callback signature:
def my_callback(tool_name: str, args: dict, result: str, task_id: str,
duration_ms: int, **kwargs):
| Parameter | Type | Description |
|---|---|---|
tool_name | str | Name of the tool that just executed |
args | dict | The arguments the model passed to the tool |
result | str | The tool's return value (always a JSON string) |
task_id | str | Session/task identifier. Empty string if not set. |
duration_ms | int | How long the tool's dispatch took, in milliseconds (measured with time.monotonic() around registry.dispatch()). |
Fires: In model_tools.py, inside handle_function_call(), after the tool's handler returns. Fires once per tool call. Does not fire if the tool raised an unhandled exception (the error is caught and returned as an error JSON string instead, and post_tool_call fires with that error string as result).
Return value: Ignored.
Use cases: Logging tool results, metrics collection, tracking tool success/failure rates, latency dashboards, per-tool budget alerts, sending notifications when specific tools complete.
Example — track tool usage metrics:
from collections import Counter, defaultdict
import json
_tool_counts = Counter()
_error_counts = Counter()
_latency_ms = defaultdict(list)
def track_metrics(tool_name, result, duration_ms=0, **kwargs):
_tool_counts[tool_name] += 1
_latency_ms[tool_name].append(duration_ms)
try:
parsed = json.loads(result)
if "error" in parsed:
_error_counts[tool_name] += 1
except (json.JSONDecodeError, TypeError):
pass
def register(ctx):
ctx.register_hook("post_tool_call", track_metrics)
pre_llm_call
Fires once per turn, before the tool-calling loop begins. All valid callback returns are aggregated in plugin order and injected into the current turn's user message.
Callback signature:
def my_callback(session_id: str, user_message: str, conversation_history: list,
is_first_turn: bool, model: str, platform: str, **kwargs):
| Parameter | Type | Description |
|---|---|---|
session_id | str | Unique identifier for the current session |
user_message | str | The user's original message for this turn (before any skill injection) |
conversation_history | list | Copy of the full message list (OpenAI format: [{"role": "user", "content": "..."}]) |
is_first_turn | bool | True if this is the first turn of a new session, False on subsequent turns |
model | str | The model identifier (e.g. "anthropic/claude-sonnet-4.6") |
platform | str | Where the session is running: "cli", "telegram", "discord", etc. |
Fires: In run_agent.py, inside run_conversation(), after context compression but before the main while loop. Fires once per run_conversation() call (i.e. once per user turn), not once per API call within the tool loop.
Return value: If the callback returns a dict with a "context" key, or a plain non-empty string, the text is appended to the current turn's user message. Return None for no injection.
# Inject context
return {"context": "Recalled memories:\n- User likes Python\n- Working on noora-agent"}
# Plain string (equivalent)
return "Recalled memories:\n- User likes Python"
# No injection
return None
Where context is injected: Always the user message, never the system prompt. This preserves the prompt cache — the system prompt stays identical across turns, so cached tokens are reused. The system prompt is Noora's territory (model guidance, tool enforcement, personality, skills). Plugins contribute context alongside the user's input.
The clean user-message content remains unchanged. For replay and prompt-cache stability, Noora may persist the exact API-bound message, including plugin-injected context, in the row's api_content sidecar.
When multiple plugins return context, their outputs are joined with double newlines in plugin discovery order (alphabetical by directory name).
Use cases: Memory recall, RAG context injection, guardrails, per-turn analytics.
Example — memory recall:
import httpx
MEMORY_API = "https://your-memory-api.example.com"
def recall(session_id, user_message, is_first_turn, **kwargs):
try:
resp = httpx.post(f"{MEMORY_API}/recall", json={
"session_id": session_id,
"query": user_message,
}, timeout=3)
memories = resp.json().get("results", [])
if not memories:
return None
text = "Recalled context:\n" + "\n".join(f"- {m['text']}" for m in memories)
return {"context": text}
except Exception:
return None
def register(ctx):
ctx.register_hook("pre_llm_call", recall)
Example — guardrails:
POLICY = "Never execute commands that delete files without explicit user confirmation."
def guardrails(**kwargs):
return {"context": POLICY}
def register(ctx):
ctx.register_hook("pre_llm_call", guardrails)
post_llm_call
Fires once per turn, after the tool-calling loop completes and the agent has produced a final response. Only fires on successful turns — does not fire if the turn was interrupted.
Callback signature:
def my_callback(session_id: str, user_message: str, assistant_response: str,
conversation_history: list, model: str, platform: str, **kwargs):
| Parameter | Type | Description |
|---|---|---|
session_id | str | Unique identifier for the current session |
user_message | str | The user's original message for this turn |
assistant_response | str | The agent's final text response for this turn |
conversation_history | list | Copy of the full message list after the turn completed |
model | str | The model identifier |
platform | str | Where the session is running |
Fires: In run_agent.py, inside run_conversation(), after the tool loop exits with a final response. Guarded by if final_response and not interrupted — so it does not fire when the user interrupts mid-turn or the agent hits the iteration limit without producing a response.
Return value: Ignored.
Use cases: Syncing conversation data to an external memory system, computing response quality metrics, logging turn summaries, triggering follow-up actions.
Example — sync to external memory:
import httpx
MEMORY_API = "https://your-memory-api.example.com"
def sync_memory(session_id, user_message, assistant_response, **kwargs):
try:
httpx.post(f"{MEMORY_API}/store", json={
"session_id": session_id,
"user": user_message,
"assistant": assistant_response,
}, timeout=5)
except Exception:
pass # best-effort
def register(ctx):
ctx.register_hook("post_llm_call", sync_memory)
Example — track response lengths:
import logging
logger = logging.getLogger(__name__)
def log_response_length(session_id, assistant_response, model, **kwargs):
logger.info("RESPONSE session=%s model=%s chars=%d",
session_id, model, len(assistant_response or ""))
def register(ctx):
ctx.register_hook("post_llm_call", log_response_length)
pre_verify
Fires once per turn when the agent edited code, just before it finishes (after the built-in verify-on-stop guard). This is a user/plugin policy gate: a callback can keep the agent going — run a check, defer it, tidy the diff — instead of letting it stop.
Noora' shipped verification guidance is not a default pre_verify hook. It is appended to the evidence-based verify-on-stop nudge when edited code lacks fresh verification evidence, so it does not create a second default continuation path. Set agent.verify_guidance: false to keep that built-in evidence nudge terse.
Callback signature:
def my_callback(session_id: str, platform: str, model: str, coding: bool,
attempt: int, final_response: str, changed_paths: list, **kwargs):
| Parameter | Type | Description |
|---|---|---|
session_id | str | Unique identifier for the current session |
platform | str | Where the session is running ("cli", "telegram", …) |
model | str | The model identifier |
coding | bool | Whether the turn is in the coding posture (in a code workspace) — scope your hook on this |
attempt | int | How many times this turn has already been nudged (0 on the first) — self-throttle on this |
final_response | str | The answer the agent is about to deliver |
changed_paths | list | Files the agent edited this turn (sorted, always non-empty here) |
Scope a hook to the coding context by checking coding and make it one-shot with attempt (shell hooks read both from .extra), the same way a pre_tool_call hook scopes on tool_name — so you can register several pre_verify hooks, each firing only where it should.
Fires: In agent/conversation_loop.py, at the point the agent would accept a final answer, immediately after the verify-on-stop check — but only when the agent edited code this turn and at least one pre_verify hook is registered.
Return value — keep the agent going:
return {"action": "continue", "message": "Run the formatter on your changes, then finish."}
The message is appended as a synthetic user turn and the loop runs again. The Claude-Code Stop shape ({"decision": "block", "reason": "..."}, where blocking the stop means keep going) is accepted too. A directive with no message — or any other return — lets the turn finish.
Bounded: consecutive continue directives in one turn are capped by agent.max_verify_nudges (default 3), so a hook that always says continue can never trap the loop. The attempted answer is kept in history but not surfaced to the user while the agent is being nudged.
Make it idempotent: the hook re-fires after each nudge, so gate on attempt (if attempt: return None) — otherwise it just nudges until the bound is hit.
Use cases: defer tests/lints during creative iteration, require green checks for certain paths, block "done" until a changelog entry exists, run a project-specific verification checklist.
Example — defer checks on creative UI work, scoped + one-shot:
UI = (".tsx", ".jsx", ".css", ".scss")
def defer_ui_checks(coding, attempt, changed_paths, **kwargs):
if attempt or not coding:
return None # one-shot, coding only
if not all(p.endswith(UI) for p in changed_paths):
return None # only pure-UI edits
return {
"action": "continue",
"message": "This is UI work — don't run tests/lints yet; ask the user to "
"eyeball it first, and clean the diff before any commit.",
}
def register(ctx):
ctx.register_hook("pre_verify", defer_ui_checks)
For standing guidance that should shape the built-in missing-evidence nudge, use agent.verify_guidance. For broader coding posture rules that don't need to gate verification, prefer agent.coding_instructions in config.yaml — it rides the coding brief and costs no extra turn.
transform_api_error_classification
Fires once per failed API call, at the top of agent/error_classifier.classify_api_error(), before the built-in pipeline. Provider plugins use it to own their provider's error quirks without core patches. It is behavior-changing (transform family): the returned classification drives retry, compression, credential rotation, and fallback routing.
Callbacks receive the parsed error context as kwargs — provider (self-scope on this), model, status_code, error_type, error_code, error_message, error_body, error, approx_tokens, context_length, num_messages. Return None to decline, or a dict to claim the error:
return {"reason": "model_not_found", # required: a FailoverReason name
"retryable": False, "should_fallback": True} # optional recovery-hint overrides
Dispatch is run-all-then-pick-first: every callback runs, failures are isolated, and the first valid result in registration order wins (valid-but-losing results log a runtime warning). Invalid dicts and unknown reasons are skipped, so a broken plugin can never break classification.
Privacy: error_message and error_body may carry unredacted provider data. Python plugins only — shell registrations are refused at config parse with a warning.
on_session_start
Fires once when a brand-new session is created. Does not fire on session continuation (when the user sends a second message in an existing session).
Callback signature:
def my_callback(session_id: str, model: str, platform: str, **kwargs):
| Parameter | Type | Description |
|---|---|---|
session_id | str | Unique identifier for the new session |
model | str | The model identifier |
platform | str | Where the session is running |
Fires: In run_agent.py, inside run_conversation(), during the first turn of a new session — specifically after the system prompt is built but before the tool loop starts. The check is if not conversation_history (no prior messages = new session).
Return value: Ignored.
Use cases: Initializing session-scoped state, warming caches, registering the session with an external service, logging session starts.
Example — initialize a session cache:
_session_caches = {}
def init_session(session_id, model, platform, **kwargs):
_session_caches[session_id] = {
"model": model,
"platform": platform,
"tool_calls": 0,
"started": __import__("datetime").datetime.now().isoformat(),
}
def register(ctx):
ctx.register_hook("on_session_start", init_session)
on_session_end
Fires at the very end of every run_conversation() call, regardless of outcome. Also fires from the CLI's exit handler if the agent was mid-turn when the user quit.
Callback signature:
def my_callback(session_id: str, completed: bool, interrupted: bool,
model: str, platform: str, **kwargs):
| Parameter | Type | Description |
|---|---|---|
session_id | str | Unique identifier for the session |
completed | bool | True if the agent produced a final response, False otherwise |
interrupted | bool | True if the turn was interrupted (user sent new message, /stop, or quit) |
model | str | The model identifier |
platform | str | Where the session is running |
Fires: In two places:
run_agent.py— at the end of everyrun_conversation()call, after all cleanup. Always fires, even if the turn errored.cli.py— in the CLI's atexit handler, but only if the agent was mid-turn (_agent_running=True) when the exit occurred. This catches Ctrl+C and/exitduring processing. In this case,completed=Falseandinterrupted=True.
Return value: Ignored.
Use cases: Flushing buffers, closing connections, persisting session state, logging session duration, cleanup of resources initialized in on_session_start.
Example — flush and cleanup:
_session_caches = {}
def cleanup_session(session_id, completed, interrupted, **kwargs):
cache = _session_caches.pop(session_id, None)
if cache:
# Flush accumulated data to disk or external service
status = "completed" if completed else ("interrupted" if interrupted else "failed")
print(f"Session {session_id} ended: {status}, {cache['tool_calls']} tool calls")
def register(ctx):
ctx.register_hook("on_session_end", cleanup_session)
Example — session duration tracking:
import time, logging
logger = logging.getLogger(__name__)
_start_times = {}
def on_start(session_id, **kwargs):
_start_times[session_id] = time.time()
def on_end(session_id, completed, interrupted, **kwargs):
start = _start_times.pop(session_id, None)
if start:
duration = time.time() - start
logger.info("SESSION_DURATION session=%s seconds=%.1f completed=%s interrupted=%s",
session_id, duration, completed, interrupted)
def register(ctx):
ctx.register_hook("on_session_start", on_start)
ctx.register_hook("on_session_end", on_end)
on_session_finalize
Fires when the CLI or gateway tears down an active session — for example, when the user runs /new, the gateway GC'd an idle session, or the CLI quit with an active agent. Use it to flush state tied to the outgoing session ID. On gateway reset, the replacement session already exists before this callback runs.
Callback signature:
def my_callback(session_id: str | None, platform: str, **kwargs):
| Parameter | Type | Description |
|---|---|---|
session_id | str or None | The outgoing session ID. May be None if no active session existed. |
platform | str | "cli" or the messaging platform name ("telegram", "discord", etc.). |
Fires: In CLI/TUI teardown and in gateway reset, shutdown, or idle-expiry paths. Gateway shutdown and expiry can finalize without a matching on_session_reset.
Return value: Ignored.
Use cases: Persist final session metrics before the session ID is discarded, close per-session resources, emit a final telemetry event, drain queued writes.
on_session_reset
Fires at a CLI or TUI session boundary, or when the gateway swaps in a new session key for an active chat. This lets plugins react to cleared conversation state without waiting for the next on_session_start.
Callback signature:
def my_callback(session_id: str, platform: str, **kwargs):
| Parameter | Type | Description |
|---|---|---|
session_id | str | The new session's ID (already rotated to the fresh value). |
platform | str | "cli", "tui", or the messaging platform name. |
reason | str, optional | Present on CLI and gateway reset paths. |
old_session_id | str, optional | Gateway-only outgoing session ID. |
new_session_id | str, optional | Gateway-only replacement session ID. |
Fires: CLI supplies session_id, platform, and reason; TUI supplies session_id and platform; gateway adds reason, old_session_id, and new_session_id after allocating the replacement key. On gateway reset, the order is: create and persist the replacement → on_session_finalize(old_id) → on_session_reset(new_id) → on_session_start(new_id) on the first inbound turn.
Return value: Ignored.
Use cases: Reset per-session caches keyed by session_id, emit "session rotated" analytics, prime a fresh state bucket.
See the Build a Plugin guide for the full walkthrough including tool schemas, handlers, and advanced hook patterns.
subagent_start
Fires once per child agent after delegate_task has constructed the child AIAgent and before that child is run. Whether you delegate a single task or a batch of three, this hook fires once for each child.
This hook is specific to delegation/subagent lifecycle. It is not a universal "before any agent invocation" gate for gateway, CLI, cron, batch, MoA, or other runner-originated agent executions.
Callback signature:
def my_callback(parent_session_id: str | None,
parent_turn_id: str,
parent_subagent_id: str | None,
child_session_id: str | None,
child_subagent_id: str,
child_role: str,
child_goal: str,
**kwargs):
| Parameter | Type | Description |
|---|---|---|
parent_session_id | str | None | Session ID of the delegating parent agent. |
parent_turn_id | str | Turn ID of the parent agent turn that requested delegation, if available. |
parent_subagent_id | str | None | Parent subagent ID when this child was spawned by another subagent; None for top-level parent agents. |
child_session_id | str | None | Session ID allocated for the child agent. |
child_subagent_id | str | Stable subagent ID used by delegation observability and controls. |
child_role | str | Effective child role after delegation policy is applied, for example "leaf" or "orchestrator". |
child_goal | str | Delegated goal/prompt that the child agent will execute. |
Fires: In tools/delegate_tool.py, inside _build_child_agent(), after the child AIAgent has been constructed and annotated with subagent identity metadata, and before _run_single_child() runs the child.
Return value: Ignored. This is an observer hook only; returning a value does not block or mutate the child agent run.
Use cases: Logging subagent creation, mapping parent/child session relationships, tracking nested delegation trees, emitting pre-run audit records, pre-allocating per-child observability resources.
Example — log subagent creation:
import logging
logger = logging.getLogger(__name__)
def log_subagent_start(
parent_session_id,
parent_turn_id,
child_session_id,
child_subagent_id,
child_role,
child_goal,
**kwargs,
):
logger.info(
"SUBAGENT_START parent=%s turn=%s child_session=%s child=%s role=%s goal=%r",
parent_session_id,
parent_turn_id,
child_session_id,
child_subagent_id,
child_role,
child_goal[:200],
)
def register(ctx):
ctx.register_hook("subagent_start", log_subagent_start)
subagent_start is useful for delegation observability, but it is not a blocking policy hook. To block delegation before a child is built, use pre_tool_call to block the delegate_task tool call.
subagent_stop
Fires once per child agent after delegate_task finishes. Whether you delegated a single task or a batch of three, this hook fires once for each child, serialised on the parent thread.
Callback signature:
def my_callback(parent_session_id: str, child_role: str | None,
child_summary: str | None, child_status: str,
tool_call_history: list[dict], duration_ms: int, **kwargs):
| Parameter | Type | Description |
|---|---|---|
parent_session_id | str | Session ID of the delegating parent agent |
child_role | str | None | Orchestrator role tag set on the child (None if the feature isn't enabled) |
child_summary | str | None | The final response the child returned to the parent |
child_status | str | "completed", "failed", "interrupted", or "error" |
tool_call_history | list[dict] | Ordered metadata-only tool calls: tool_name, bounded tool_input, input_bytes, output_bytes, and status; raw inputs and outputs are excluded |
duration_ms | int | Wall-clock time spent running the child, in milliseconds |
Fires: In tools/delegate_tool.py, after ThreadPoolExecutor.as_completed() drains all child futures. Firing is marshalled to the parent thread so hook authors don't have to reason about concurrent callback execution.
Return value: Ignored.
Use cases: Logging orchestration activity, accumulating child durations for billing, writing post-delegation audit records.
Example — log orchestrator activity:
import logging
logger = logging.getLogger(__name__)
def log_subagent(parent_session_id, child_role, child_status, duration_ms, **kwargs):
logger.info(
"SUBAGENT parent=%s role=%s status=%s duration_ms=%d",
parent_session_id, child_role, child_status, duration_ms,
)
def register(ctx):
ctx.register_hook("subagent_stop", log_subagent)
With heavy delegation (e.g. orchestrator roles × 5 leaves × nested depth), subagent_stop fires many times per turn. Keep your callback fast; push expensive work to a background queue.
pre_gateway_dispatch
Fires once per incoming MessageEvent in the gateway, after the internal-event guard but before auth/pairing and agent dispatch. This is the interception point for gateway-level message-flow policies (listen-only windows, human handover, per-chat routing, etc.) that don't fit cleanly into any single platform adapter.
Callback signature:
def my_callback(event, gateway, session_store, **kwargs):
| Parameter | Type | Description |
|---|---|---|
event | MessageEvent | The normalized inbound message (has .text, .source, .message_id, .internal, etc.). |
gateway | GatewayRunner | The active gateway runner, so plugins can call gateway.adapters[platform].send(...) for side-channel replies (owner notifications, etc.). |
session_store | SessionStore | For silent transcript ingestion via session_store.append_to_transcript(...). |
Fires: In gateway/run.py, inside GatewayRunner._handle_message(), immediately after is_internal is computed. Internal events skip the hook entirely (they are system-generated — background-process completions, etc. — and must not be gate-kept by user-facing policy).
Return value: None or a dict. The first recognized action dict wins; remaining plugin results are ignored. Exceptions in plugin callbacks are caught and logged; the gateway always falls through to normal dispatch on error.
| Return | Effect |
|---|---|
{"action": "skip", "reason": "..."} | Drop the message — no agent reply, no pairing flow, no auth. Plugin is assumed to have handled it (e.g. silent-ingested into the transcript). |
{"action": "rewrite", "text": "new text"} | Replace event.text, then continue normal dispatch with the modified event. Useful for collapsing buffered ambient messages into a single prompt. |
{"action": "allow"} / None | Normal dispatch — runs the full auth / pairing / agent-loop chain. |
Use cases: Listen-only group chats (only respond when tagged; buffer ambient messages into context); human handover (silent-ingest customer messages while owner handles the chat manually); per-profile rate limiting; policy-driven routing.
Example — drop unauthorized DMs silently without triggering the pairing code:
def deny_unauthorized_dms(event, **kwargs):
src = event.source
if src.chat_type == "dm" and not _is_approved_user(src.user_id):
return {"action": "skip", "reason": "unauthorized-dm"}
return None
def register(ctx):
ctx.register_hook("pre_gateway_dispatch", deny_unauthorized_dms)
Example — rewrite an ambient-message buffer into a single prompt on mention:
_buffers = {}
def buffer_or_rewrite(event, **kwargs):
key = (event.source.platform, event.source.chat_id)
buf = _buffers.setdefault(key, [])
if _bot_mentioned(event.text):
combined = "\n".join(buf + [event.text])
buf.clear()
return {"action": "rewrite", "text": combined}
buf.append(event.text)
return {"action": "skip", "reason": "ambient-buffered"}
def register(ctx):
ctx.register_hook("pre_gateway_dispatch", buffer_or_rewrite)
gateway_platform_event
Fires for supported platform-native events only after the gateway's normal, profile-scoped authorization check succeeds. The callback receives plain dictionaries; raw SDK objects, adapter handles, bot clients, and callback contexts are never part of this stable contract.
Telegram message reactions were the first supported event; message edits, deletes, and thread lifecycle events followed:
def on_platform_event(platform, event_type, payload, **kwargs):
if platform == "telegram" and event_type == "reaction":
print(payload["chat_id"], payload["message_id"], payload["emojis"])
elif event_type == "message_edited":
print(platform, payload["chat_id"], payload["message_id"], payload["text"])
def register(ctx):
ctx.register_hook("gateway_platform_event", on_platform_event)
| Parameter | Type | Description |
|---|---|---|
platform | str | Stable platform id ("telegram", "discord"). |
event_type | str | Event-local contract id (see the table below). |
payload | dict | Event-type-specific fields, documented per event type below. |
Every payload is additive and event-specific; there is no monolithic gateway payload version. All ids are strings; missing/unavailable fields are None, never guessed. Malformed events and events whose source cannot be authorized are dropped (fail closed). A transient Telegram Application rebuild re-registers the observer together with the core handlers.
Per-event payload contracts (v1, additive):
event_type | Platforms | Payload fields |
|---|---|---|
reaction | telegram | emojis: list[str], custom_emoji_ids: list[str], chat_id: str, message_id: str, thread_id: str | None (Telegram reaction updates carry no topic id, so currently always None). |
message_edited | telegram, discord | chat_id: str, message_id: str, thread_id: str | None, text: str | None (edited text or caption, bounded; None for media-only edits or when uncached), edited_at: str | None (ISO 8601). |
message_deleted | discord | chat_id: str, message_id: str, thread_id: str | None, author_id: str | None. Discord's delete event does not identify the deleter; the authorized source is the deleted message's author, and uncached deletions never fire. |
thread_created | discord | thread_id: str, parent_chat_id: str | None, name: str | None, owner_id: str | None. |
thread_renamed | discord | thread_id: str, parent_chat_id: str | None, old_name: str | None, new_name: str. Fired only when the name actually changed; other thread updates (archive, slowmode, tags) are dropped. Discord's thread-update event carries no actor, so the thread owner is the authorized source. |
The bot's own progressive message edits (streaming) never fire message_edited on Discord — bot-authored events are dropped at the fire-site.
This hook is observer-only: it does not add raw-event access or adapter access. Raw SDK payload access is deliberately not shipped — adapter SDK objects change shape without notice and would become un-evolvable API surface; where genuinely needed it requires its own explicit capability (gateway.raw_events) with a "no stability guarantee" label and its own design (tracked in #64228). For acting on a platform (adding a reaction, renaming a thread), use the capability-gated ctx.platform_actions facade documented in the plugins guide — it is gated off by default behind the gateway.platform_actions capability. PluginContext.dispatch_tool() can only call tools registered in the tool registry; send_message is intentionally not registered there (its transport is reserved for explicit CLI, cron, kanban, and MCP delivery paths). A future outbound-delivery contract must first provide stable delivered content/handles across all adapters; this slice does not pre-register an inert gateway_message_delivered hook.
pre_approval_request
Fires before an approval decision is requested. It covers prompted surfaces—interactive CLI, Ink TUI, gateway platforms, and ACP clients—and approvals.mode=smart decisions made without a human prompt (surface="smart"). In smart mode, the hook runs before the auxiliary LLM is called.
This is the right place to wire a custom notifier — for example, a macOS menu-bar app that pops an allow/deny notification, or an audit log that records every approval request with context.
Callback signature:
def my_callback(
command: str,
description: str,
pattern_key: str,
pattern_keys: list[str],
session_key: str,
surface: str,
**kwargs,
):
| Parameter | Type | Description |
|---|---|---|
command | str | Terminal command or execute_code script being assessed. Smart and gateway payloads are redacted before observer dispatch. Smart observer redaction is mandatory even when security.redact_secrets is disabled; if redaction fails, smart hooks are skipped. |
description | str | Human-readable reason(s) the command is flagged (combined when multiple patterns match) |
pattern_key | str | Primary pattern key that triggered the approval (e.g. "rm_rf", "sudo") |
pattern_keys | list[str] | All pattern keys that matched |
session_key | str | Session identifier, useful for scoping notifications per-chat |
surface | str | "cli" for interactive CLI/TUI prompts, "gateway" for async platform approvals, or "smart" for auxiliary-LLM auto approve/deny decisions |
Return value: ignored. Hooks here are observer-only; they cannot veto or pre-answer the approval. Use pre_tool_call to block a tool before it reaches the approval system.
Use cases: Desktop notifications, push alerts, audit logging, Slack webhooks, escalation routing, metrics.
Example — desktop notification on macOS:
import subprocess
def notify_approval(command, description, session_key, **kwargs):
title = "Noora needs approval"
body = f"{description}: {command[:80]}"
subprocess.Popen([
"osascript", "-e",
f'display notification "{body}" with title "{title}"',
])
def register(ctx):
ctx.register_hook("pre_approval_request", notify_approval)
post_approval_response
Fires after a prompted or smart approval decision, after a prompt times out, or when the gateway cannot deliver the approval notification. Notification failure emits choice="notify_failed" before any approval decision exists.
Callback signature:
def my_callback(
command: str,
description: str,
pattern_key: str,
pattern_keys: list[str],
session_key: str,
surface: str,
choice: str,
**kwargs,
):
Same kwargs as pre_approval_request, plus:
| Parameter | Type | Description |
|---|---|---|
choice | str | Prompted surfaces use "once", "session", "always", "deny", "timeout", or "notify_failed"; smart decisions use "smart_approve" or "smart_deny" |
decided_by | str | "aux_llm" for smart decisions; absent on prompted surfaces |
Return value: ignored.
Use cases: Close the matching desktop notification, record the final decision in an audit log, update metrics, roll forward a rate limiter.
def log_decision(command, choice, session_key, **kwargs):
logger.info("approval %s: %s for session %s", choice, command[:60], session_key)
def register(ctx):
ctx.register_hook("post_approval_response", log_decision)
pre_transcription
Fires inside the STT dispatcher (tools.transcription_tools.transcribe_audio) after the provider has been resolved and before any backend is invoked, whether that backend is built-in, a type: command provider, or a plugin-registered provider. Lets a plugin steer the transcription request itself instead of only observing the transcript afterwards.
Callback signature:
def my_callback(
file_path: str,
provider: str,
model: str | None,
language: str | None,
prompt: str | None,
source: str | None,
**kwargs,
) -> dict | None:
| Parameter | Type | Description |
|---|---|---|
file_path | str | Absolute path to the audio file about to be transcribed. Read-only. |
provider | str | Resolved STT provider (local, groq, openai, mistral, xai, elevenlabs, deepinfra, local_command, a command provider name, or a plugin provider name). |
model | str | None | Model resolved so far, or None when the backend default applies. |
language | str | None | Language from the provider's config section, or None. |
prompt | str | None | The static stt.prompt value, or None. |
source | str | None | Caller surface label (gateway, voice_mode, …). Observability only, not used for dispatch. |
Return value: a dict with any of "prompt", "language", "model" mapped to strings, or None to leave the request unchanged. Non-string values, unknown keys, and file_path are ignored (file_path attempts are logged as a warning). Results are applied in registration order, last-writer-wins per field, on top of the stt.prompt config value. Returning "" for prompt clears the configured prompt for that request.
Use cases: Inject a per-user or per-chat vocabulary list before the audio is uploaded, force language from the caller's locale, downgrade model for long recordings, route noisy sources to a different model.
VOCAB = "Noora, Teknium, Noora, kanban"
def add_vocab(provider, prompt, source, **kwargs):
if source != "gateway":
return None
return {"prompt": f"{prompt}. {VOCAB}" if prompt else VOCAB}
def register(ctx):
ctx.register_hook("pre_transcription", add_vocab)
Not every backend accepts a prompt. local maps it to faster-whisper's initial_prompt; openai, groq, mistral, and deepinfra send it as prompt; xai, elevenlabs, local_command, and type: command providers log at DEBUG and transcribe without it. See the provider support table for the full matrix and the privacy boundary. Hook-plumbing errors are fail-open: the dispatch continues with the unmodified request.
transform_tool_result
Fires after a tool returns and before the result is appended to the conversation. Lets a plugin rewrite ANY tool's result string — not just terminal output — before the model sees it.
Callback signature:
def my_callback(tool_name: str, args: dict, result: str, task_id: str, **kwargs) -> str | None:
The full payload also includes session_id, tool_call_id, turn_id, api_request_id, duration_ms, status, error_type, and error_message. result is the final result returned by tool dispatch; it and args can contain arbitrary user/tool content and secrets.
Return value: The first str replaces the result (including an empty string); None leaves it unchanged.
Use cases: Redact organization-specific PII from web_extract output, wrap long JSON tool responses in a summary header, inject retrieval-augmented hints into read_file results, rewrite delegate_task subagent reports into a project-specific schema.
import re
SECRET = re.compile(r"sk-[A-Za-z0-9]{32,}")
def redact_secrets(tool_name, result, **kwargs):
if SECRET.search(result):
return SECRET.sub("[REDACTED]", result)
return None
def register(ctx):
ctx.register_hook("transform_tool_result", redact_secrets)
Applies to every tool. For terminal-only rewriting see transform_terminal_output below — it is narrower, runs before transform_tool_result, and its replacement is still subject to the terminal tool's final output limit.
transform_terminal_output
Fires inside the terminal tool after foreground process capture has already been bounded by the environment, and before the final output limit. It lets plugins replace the captured stdout/stderr; the replacement is still subject to the final output limit.
Callback signature:
def my_callback(
command: str,
output: str,
returncode: int,
task_id: str,
env_type: str,
**kwargs,
) -> str | None:
| Parameter | Type | Description |
|---|---|---|
command | str | The shell command that produced the output. |
output | str | Combined stdout/stderr after bounded process capture. |
returncode | int | Process return code. |
task_id | str | Effective task identifier, or an empty string. |
env_type | str | Execution-environment type. |
Return value: First str replaces the output; None leaves it unchanged. Command and output can contain credentials or other sensitive data.
def summarize_find(command, output, **kwargs):
if command.startswith("find ") and len(output) > 50_000:
lines = output.count("\n")
head = "\n".join(output.splitlines()[:40])
return f"{head}\n\n[summary: {lines} paths total, showing first 40]"
return None
def register(ctx):
ctx.register_hook("transform_terminal_output", summarize_find)
Pairs with transform_tool_result, which runs afterward for every tool, including terminal.
transform_llm_output
Fires once per turn after the tool-calling loop completes and the model has produced a final response, before that response is delivered to the user (CLI, gateway, or programmatic caller). Lets a plugin rewrite the assistant's final text using classical-programming methods — no extra inference tokens burned on SOUL flavor text or a skill-driven transform.
Callback signature:
def my_callback(
response_text: str,
session_id: str,
model: str,
platform: str,
**kwargs,
) -> str | None:
| Parameter | Type | Description |
|---|---|---|
response_text | str | The assistant's final response text for this turn. |
session_id | str | Session ID for this conversation (may be empty for one-shot runs). |
model | str | Model name that produced the response (e.g. anthropic/claude-sonnet-4.6). |
platform | str | Delivery platform (cli, telegram, discord, …; empty when unset). |
Return value: Non-empty str to replace the response text, None or empty string to leave it unchanged. First non-empty string wins when multiple plugins register. Unlike the tool and terminal transforms, an empty string is not accepted as a replacement.
Use cases: Apply a personality/vocabulary transform (pirate-speak, Spongebob), redact user-specific identifiers from the final text, append a project-specific signature footer, enforce a house style guide without burning tokens on SOUL instructions.
When CLI streaming is enabled, an append-only transform is printed after the streamed body. A transform that replaces the response is printed in full after the streamed body, labeled as a post-stream transformation, so replacement content is never silently lost.
import os, re
def spongebob(response_text, **kwargs):
if os.environ.get("SPONGEBOB_MODE") != "on":
return None # pass through unchanged
return re.sub(r"!", "!! Tartar sauce!", response_text)
def register(ctx):
ctx.register_hook("transform_llm_output", spongebob)
The hook is guarded on a non-empty, non-interrupted response — it will not fire on stop-button interrupts or empty turns. Exceptions are logged as warnings and do not break agent execution.
API-request observer hooks
pre_api_request
Fires for each provider attempt immediately before sending it. This is observer-only. The legacy user_message, conversation_history, and request_messages fields are raw and intentionally unsanitized for compatibility; new consumers should prefer the sanitized request envelope.
post_api_request
Fires after a provider response has been normalized successfully. This is observer-only. Prefer the sanitized response; assistant_message is the raw normalized message, and usage contains accounting data.
api_request_error
Fires for a failed provider attempt with status/retry timing, an error object, and sanitized request. This is observer-only. Error messages may still contain provider or user data.
on_skill_lifecycle
Fires after an authoritative skill-usage state change. It is observer-only and exposes the local skill_name, provenance, correlation IDs, usage count, and reuse flags.
Kanban lifecycle observers
kanban_task_claimed
Fires after the claim commit in the dispatcher process, immediately before worker spawn.
kanban_task_completed
Fires after completion and cleanup, usually in the worker process. Its summary can contain project or user content.
kanban_task_blocked
Fires after a normal blocked transition. The dependency-wait path invokes it before that write transaction exits. Its reason can contain project or user content.
All three kanban hooks are observer-only and carry task_id, profile_name, board, assignee, and run_id; completed adds summary, and blocked adds reason.
Kanban worker-lifecycle, task-mutation, and dispatch observers
Five additional observers (RFC #58548) extend the kanban family. All are observer-only, fire after the relevant transaction commits, and short-circuit on has_hook — with no subscriber, dispatch behavior is unchanged. Task-scoped hooks carry the same common fields as the hooks above.
on_kanban_worker_spawned— afterspawn_fnreturns and the worker PID is persisted. Addsworker_pid(may beNone) andworkspace_path. Runs inside the dispatch lock; keep callbacks fast.on_kanban_worker_exited— tick-derived, whendetect_crashed_workersreclaims a dead-PID task. Addsworker_pid,exit_kind,exit_code,outcome,retry_status.on_kanban_worker_stale_claim— when a TTL-expired claim is reclaimed; live-PID extensions don't fire. Addsworker_pid,heartbeat_stale,retry_status.on_kanban_task_updated— after a committed task-field write outside the claim/complete/block lifecycle (assign_task, model/reasoning overrides, dashboard editors). Addschanged_fields— field names only, never values.on_kanban_dispatch_tick— once per dispatcher tick, strictly after the dispatch lock is released, including idle and lock-contended ticks. Payload:board,profile_name,dry_run,outcome,result.
Shell Hooks
Declare shell-script hooks in your ~/.noora/config.yaml and Noora will run them as subprocesses whenever the corresponding plugin-hook event fires — in both CLI and gateway sessions. No Python plugin authoring required.
Use shell hooks when you want a drop-in, single-file script (Bash, Python, anything with a shebang) to:
- Block or modify a tool call — reject dangerous
terminalcommands, enforce per-directory policies, require approval for destructivewrite_file/patchoperations, or rewrite arguments (sanitize paths, inject defaults) before the tool runs. - Run after a tool call — auto-format Python or TypeScript files that the agent just wrote, log API calls, trigger a CI workflow.
- Inject context into the next LLM turn — prepend
git statusoutput, the current weekday, or retrieved documents to the user message (seepre_llm_call). - Observe lifecycle events — write a log line when a subagent completes (
subagent_stop) or a session starts (on_session_start).
Shell hooks are registered by calling agent.shell_hooks.register_from_config(cfg) at both CLI startup (noora_cli/main.py) and gateway startup (gateway/run.py). They compose naturally with Python plugin hooks — both flow through the same dispatcher.
Comparison at a glance
| Dimension | Shell hooks | Plugin hooks | Gateway hooks |
|---|---|---|---|
| Declared in | hooks: block in ~/.noora/config.yaml | register() in a plugin.yaml plugin | HOOK.yaml + handler.py directory |
| Lives under | ~/.noora/agent-hooks/ (by convention) | ~/.noora/plugins/<name>/ | ~/.noora/hooks/<name>/ |
| Language | Any (Bash, Python, Go binary, …) | Python only | Python only |
| Runs in | CLI + Gateway | CLI + Gateway | Gateway only |
| Events | VALID_HOOKS (incl. subagent_stop) | VALID_HOOKS | Gateway lifecycle (gateway:startup, agent:*, command:*) |
| Can block a tool call | Yes (pre_tool_call) | Yes (pre_tool_call) | No |
| Can inject LLM context | Yes (pre_llm_call) | Yes (pre_llm_call) | No |
| Consent | First-use prompt per (event, command) pair | Implicit (Python plugin trust) | Implicit (dir trust) |
| Inter-process isolation | Yes (subprocess) | No (in-process) | No (in-process) |
Configuration schema
hooks:
<event_name>: # Must be in VALID_HOOKS
- matcher: "<regex>" # Optional; used for pre/post_tool_call only
command: "<shell command>" # Required; runs via shlex.split, shell=False
timeout: <seconds> # Optional; default 60, capped at 300
fail_closed: <bool> # Optional; default false. pre_tool_call only.
# `failClosed` also accepted (Cursor/Claude Code compat)
hooks_auto_accept: false # See "Consent model" below
Event names must be one of the plugin hook events; typos produce a "Did you mean X?" warning and are skipped. Unknown keys inside a single entry are ignored; missing command is a skip-with-warning. timeout > 300 is clamped with a warning. fail_closed: true on an event other than pre_tool_call warns and is ignored (only blocking-capable events can fail closed).
JSON wire protocol
Each time the event fires, Noora spawns a subprocess for every matching hook (matcher permitting), pipes a JSON payload to stdin, and reads stdout back as JSON.
stdin — payload the script receives:
{
"hook_event_name": "pre_tool_call",
"tool_name": "terminal",
"tool_input": {"command": "rm -rf /"},
"session_id": "sess_abc123",
"cwd": "/home/user/project",
"extra": {"task_id": "...", "tool_call_id": "..."}
}
tool_name and tool_input are null for non-tool events (pre_llm_call, subagent_stop, session lifecycle). The extra dict carries all event-specific kwargs (user_message, conversation_history, child_role, duration_ms, …). Unserialisable values are stringified rather than omitted.
stdout — optional response:
// Block a pre_tool_call (both shapes accepted; normalised internally):
{"decision": "block", "reason": "Forbidden: rm -rf"} // Claude-Code style
{"action": "block", "message": "Forbidden: rm -rf"} // Noora-canonical
// Modify a pre_tool_call — rewrite tool args before dispatch:
{"action": "modify", "args": {"new_string": "fixed content"}} // Noora-canonical
{"decision": "modify", "tool_input": {"new_string": "fixed content"}} // Claude-Code style
// Inject context for pre_llm_call:
{"context": "Today is Friday, 2026-04-17"}
// Keep the agent going at the verify gate (pre_verify); both shapes accepted:
{"action": "continue", "message": "Run the formatter, then finish."}
{"decision": "block", "reason": "Run the formatter, then finish."}
// Silent no-op — any empty / non-matching output is fine:
Malformed JSON, non-zero exit codes, and timeouts log a warning but never abort the agent loop.
Exit code 2 = block (Claude Code / Cursor compatible)
A pre_tool_call hook that exits with code 2 blocks the tool call even when its stdout carries no block JSON. The block message is resolved in priority order:
- stdout block JSON (
reason/message), when present; - the first 400 characters of stderr;
- a generic
"Blocked by shell hook."default.
So the simplest possible blocking hook is:
#!/usr/bin/env bash
echo "policy violation: rm -rf is not permitted" >&2
exit 2
For events whose block directive is not honored (everything except pre_tool_call), exit 2 is treated like any other non-zero exit: a warning is logged and stdout is still parsed.
Fail-open vs fail-closed
By default shell hooks fail open: a spawn error, timeout, or unparseable stdout logs a warning and the action proceeds. That is the right default for observability hooks — but wrong for security gates. A crashed secret-scanner must not silently allow the tool call it was supposed to vet.
Set fail_closed: true (or failClosed: true, the Cursor/Claude Code spelling) on a pre_tool_call entry to invert that:
hooks:
pre_tool_call:
- matcher: "terminal|write_file|patch"
command: "~/.noora/agent-hooks/secret-scan.sh"
timeout: 10
fail_closed: true
With fail_closed: true, each of these now blocks the tool call with hook <command> failed closed: <reason>:
| Failure | Fail-open (default) | fail_closed: true |
|---|---|---|
| Command not found / not executable | warn, proceed | block |
| Timeout | warn, proceed | block |
| Non-JSON stdout (e.g. a stack trace) | warn, proceed | block |
Clean exit, valid no-op JSON ({}) | proceed | proceed |
fail_closed only applies to blocking-capable events (pre_tool_call today); setting it on any other event logs a warning at config-parse time and is ignored. noora hooks test reflects these semantics — the parsed line shows exactly the block shape the dispatcher would receive.
Worked examples
1. Auto-format Python files after every write
# ~/.noora/config.yaml
hooks:
post_tool_call:
- matcher: "write_file|patch"
command: "~/.noora/agent-hooks/auto-format.sh"
#!/usr/bin/env bash
# ~/.noora/agent-hooks/auto-format.sh
payload="$(cat -)"
path=$(echo "$payload" | jq -r '.tool_input.path // empty')
[[ "$path" == *.py ]] && command -v black >/dev/null && black "$path" 2>/dev/null
printf '{}\n'
The agent's in-context view of the file is not re-read automatically — the reformat only affects the file on disk. Subsequent read_file calls pick up the formatted version.
2. Block destructive terminal commands
hooks:
pre_tool_call:
- matcher: "terminal"
command: "~/.noora/agent-hooks/block-rm-rf.sh"
timeout: 5
#!/usr/bin/env bash
# ~/.noora/agent-hooks/block-rm-rf.sh
payload="$(cat -)"
cmd=$(echo "$payload" | jq -r '.tool_input.command // empty')
if echo "$cmd" | grep -qE 'rm[[:space:]]+-rf?[[:space:]]+/'; then
printf '{"decision": "block", "reason": "blocked: rm -rf / is not permitted"}\n'
else
printf '{}\n'
fi
3. Inject git status into every turn (Claude-Code UserPromptSubmit equivalent)
hooks:
pre_llm_call:
- command: "~/.noora/agent-hooks/inject-cwd-context.sh"
#!/usr/bin/env bash
# ~/.noora/agent-hooks/inject-cwd-context.sh
cat - >/dev/null # discard stdin payload
if status=$(git status --porcelain 2>/dev/null) && [[ -n "$status" ]]; then
jq --null-input --arg s "$status" \
'{context: ("Uncommitted changes in cwd:\n" + $s)}'
else
printf '{}\n'
fi
Claude Code's UserPromptSubmit event is intentionally not a separate Noora event — pre_llm_call fires at the same place and already supports context injection. Use it here.
4. Log every subagent completion
hooks:
subagent_stop:
- command: "~/.noora/agent-hooks/log-orchestration.sh"
#!/usr/bin/env bash
# ~/.noora/agent-hooks/log-orchestration.sh
log=~/.noora/logs/orchestration.log
jq -c '{ts: now, parent: .session_id, extra: .extra}' < /dev/stdin >> "$log"
printf '{}\n'
Consent model
Each unique (event, command) pair prompts the user for approval the first time Noora sees it, then persists the decision to ~/.noora/shell-hooks-allowlist.json. Subsequent runs (CLI or gateway) skip the prompt.
Three escape hatches bypass the interactive prompt — any one is sufficient:
--accept-hooksflag on the CLI (e.g.noora --accept-hooks chat)NOORA_ACCEPT_HOOKS=1environment variablehooks_auto_accept: truein~/.noora/config.yaml
Non-TTY runs (gateway, cron, CI) need one of these three — otherwise any newly-added hook silently stays un-registered and logs a warning.
Script edits are silently trusted. The allowlist keys on the exact command string, not the script's hash, so editing the script on disk does not invalidate consent. noora hooks doctor flags mtime drift so you can spot edits and decide whether to re-approve.
Manual allowlisting
Manual allowlisting is useful for non-TTY or service-account deployments where an operator cannot answer the first-use prompt interactively. The allowlist file is ~/.noora/shell-hooks-allowlist.json, and the expected format is an approvals array. Each approval records the hook event and the exact command string:
{
"approvals": [
{
"event": "post_llm_call",
"command": "/home/noora/.noora/hooks/my-hook.py"
}
]
}
The command string must match the configured hook command exactly. A path-keyed object with a sha256 field is not the expected format and will not approve the hook. Verify manual entries with noora hooks list.
The noora hooks CLI
| Command | What it does |
|---|---|
noora hooks list | Dump configured hooks with matcher, timeout, and consent status |
noora hooks test <event> [--for-tool X] [--payload-file F] | Fire every matching hook against a synthetic payload and print the parsed response |
noora hooks revoke <command> | Remove every allowlist entry matching <command> (takes effect on next restart) |
noora hooks doctor | For every configured hook: check exec bit, allowlist status, mtime drift, JSON output validity, and rough execution time |
Security
Shell hooks run with your full user credentials — same trust boundary as a cron entry or a shell alias. Treat the hooks: block in config.yaml as privileged configuration:
- Only reference scripts you wrote or fully reviewed.
- Keep scripts inside
~/.noora/agent-hooks/so the path is easy to audit. - Re-run
noora hooks doctorafter you pull a shared config to spot newly-added hooks before they register. - If your config.yaml is version-controlled across a team, review PRs that change the
hooks:section the same way you'd review CI config.
Ordering and precedence
Both Python plugin hooks and shell hooks flow through the same invoke_hook() dispatcher. Python plugins are registered first (discover_and_load()), shell hooks second (register_from_config()), so Python pre_tool_call block decisions take precedence in tie cases. The first valid block wins — the aggregator returns as soon as any callback produces {"action": "block", "message": str} with a non-empty message.
Outbound Webhooks
Outbound webhooks are the push-side mirror of the inbound webhook platform: inbound webhooks wake Noora when the world changes; outbound webhooks tell the world when Noora does something. Configure a list of HTTP endpoints and the lifecycle events they care about, and Noora POSTs a signed JSON payload to each endpoint whenever a matching event fires — no polling on the receiving end.
Typical uses:
- Notify a CI system or dashboard when an agent turn finishes (
on_session_end) - Track subagent completions across a fleet (
subagent_stop) - Feed tool activity into external monitoring (
post_tool_callwith amatcher) - Wake another Noora instance: point the URL at that instance's inbound webhook
Configuration
Add a hooks.outbound: list to ~/.noora/config.yaml:
hooks:
outbound:
- name: ci-notify # optional label for logs
url: https://ci.example.com/noora-events
events: [on_session_end, subagent_stop]
secret_env: NOORA_OUTBOUND_WEBHOOK_SECRET # env var holding the HMAC secret
timeout: 10 # per-attempt seconds (1–60)
- name: tool-monitor
url: https://metrics.example.com/hooks/noora
events: [post_tool_call]
matcher: "terminal|delegate_task" # regex, tool-scoped events only
Any event from the plugin-hook set is valid (pre_tool_call, post_tool_call, pre_llm_call, post_llm_call, on_session_start, on_session_end, subagent_start, subagent_stop, ...). Malformed entries warn and are skipped — a broken webhook never crashes the agent. Changes take effect on the next CLI session / gateway restart.
Secrets: prefer secret_env (the name of an environment variable, typically set in ~/.noora/.env) over an inline secret: literal, so the config file stays free of credentials. Entries without a secret are delivered unsigned (flagged as UNSIGNED by noora hooks list).
Wire format
Each firing POSTs a JSON body with the same top-level shape as shell hooks' stdin, plus delivery metadata:
{
"hook_event_name": "on_session_end",
"tool_name": null,
"tool_input": null,
"session_id": "sess_abc123",
"cwd": "/home/user/project",
"extra": {"completed": true, "interrupted": false, "model": "...", "platform": "cli"},
"delivery_id": "3f2c9a...",
"timestamp": "2026-07-22T14:00:00Z"
}
Headers:
| Header | Value |
|---|---|
Content-Type | application/json |
X-Noora-Event | The hook event name |
X-Noora-Delivery | Unique id per delivery — same value as delivery_id in the body |
X-Noora-Signature-256 | sha256=<hex> — HMAC-SHA256 of the raw body, GitHub-style; only present when a secret is configured |
Verify the signature exactly as you would a GitHub webhook:
import hashlib, hmac
def verify(body: bytes, header: str, secret: str) -> bool:
expected = "sha256=" + hmac.new(secret.encode(), body, hashlib.sha256).hexdigest()
return hmac.compare_digest(expected, header)
Because delivery_id and timestamp live inside the signed body, a verified receiver also gets replay protection for free:
- Dedupe on
delivery_id(or the matchingX-Noora-Deliveryheader) — remember recently seen ids and skip duplicates. Noora retries failed deliveries once, so the same id can legitimately arrive twice. - Reject stale events by checking
timestampagainst your clock with a tolerance window (5 minutes is the common default). An attacker replaying a captured request can't forge a fresh timestamp without the secret.
Delivery semantics
- Fire-and-forget, off the hot path. Events are serialized and queued instantly; a single background thread performs the HTTP POSTs. A slow or dead endpoint can never stall a tool call or an agent turn.
- Notify-only. Unlike shell hooks, outbound webhooks cannot block tool calls or inject context — the response body is ignored. They observe, never steer.
- Bounded retries. Connection errors and 5xx responses are retried once with backoff; 4xx responses are not retried (the receiver said the request itself is wrong). Failures are logged and dropped — delivery is best-effort, not guaranteed.
- Redirects are never followed. A 3xx response is treated as a misconfiguration and logged — following a redirected POST would silently drop the signed payload. Point the
urlat the final endpoint. - Bounded queue. If the queue backs up (dead endpoint, event storm), new events are dropped with a warning rather than consuming unbounded memory.
- No consent prompt. Outbound targets execute no code on your machine — they receive data at a URL you configured.
NOORA_SAFE_MODE=1still skips registration, same as plugins and shell hooks. Note that payloads include tool inputs and event metadata, so only point targets at endpoints you trust, and preferhttps://.
noora hooks list shows configured outbound targets alongside shell hooks, including whether each target is signed.