agentaudit — Python SDK

Tamper-evident audit logging for AI agents, built for EU AI Act Article 12 record-keeping. Three lines of code get events flowing to your AgentAudit backend; a hash chain over every event makes tampering detectable after the fact.

pip install agentaudit-python   # PyPI distribution name; import is still `agentaudit`

import agentaudit

agentaudit.init(api_key="aa_live_sk_...", agent_id="my-support-agent")
agentaudit.log_event(event_type="decision", action="route_to_human")

Get your API key

From your AgentAudit dashboard: sign up, create a project, then go to Settings → API Keys → Create key. The raw key (starts with aa_live_sk_) is shown exactly once — copy it immediately. It is never recoverable after that; losing it means revoking it and creating a new one.

Store it as an environment variable, not in source:

import os
import agentaudit

agentaudit.init(api_key=os.environ["AGENTAUDIT_API_KEY"], agent_id="my-support-agent")

Three ways to log events

@agentaudit.trace — simplest, framework-agnostic

@agentaudit.trace
def search_documents(query: str, top_k: int = 5) -> list:
    return vector_db.similarity_search(query, k=top_k)

Logs a tool_call event per call: action is the function's qualified name, input_hash/output_hash are SHA-256 digests of the arguments and return value (never raw), metadata.duration_ms is execution time. A raised exception is logged as severity="critical" with metadata.error, and always still propagates — @trace only observes, it never changes what the wrapped function does. Works on sync and async functions.

LangChainHandler — for LangChain / LangGraph

from agentaudit.integrations import LangChainHandler  # pip install agentaudit-python[langchain]

chain.invoke(inputs, config={"callbacks": [LangChainHandler()]})

Handles on_llm_start/on_llm_end (and on_chat_model_start, which chat models call instead), on_llm_error, on_tool_start/on_tool_end, on_tool_error, and on_chain_error. LLM calls log model name and token usage only — no prompt or response content, hashed or otherwise. This is stricter than the SDK's default elsewhere: a callback wired into every LLM call in a chain has no per-call decision behind it, so it defaults to the safest reading. Tool calls are hashed, matching @trace.

All three error paths log the identical shape: event_type="error", severity="critical", metadata={"error": {"type": ..., "message": ...}}. on_tool_error fires even when the surrounding chain catches the exception and completes normally — a failure the chain recovered from is still worth an audit trail.

Not implemented: a start/end event for the chain run as a whole (that's session-grouping territory, not a per-call audit gap — every LLM call, tool call, and error inside the chain is already captured on its own).

agentaudit.log_event() — manual, for anything custom

agentaudit.log_event(
    event_type="decision",
    action="route_to_human",
    metadata={"reason": "low_confidence", "confidence_score": 0.23},
    severity="warning",
)

event_type is one of tool_call, llm_call, decision, data_access, error, custom. severity is one of info, warning, critical (default info). Pass inputs=/outputs= to get the same hashing guarantee @trace applies automatically.

Privacy

Inputs and outputs are SHA-256 hashed, never sent raw, by default (hash_inputs=True). metadata is the one exception — it is not hashed, because it's yours to control; whatever you put there is sent and stored as-is. Pass hash_inputs=False to init() to opt into raw logging instead; raw values then travel under the reserved keys metadata.raw_input and metadata.raw_output, since the event schema has no top-level field for them. init(environment=...) is likewise recorded as metadata.environment.

Delivery

Capture never blocks: log_event appends to an in-memory queue and returns (~0.05 ms). A daemon thread owning its own asyncio loop and httpx.AsyncClient drains that queue every flush_interval seconds, or as soon as batch_size events are waiting — whichever comes first. One implementation serves both sync and async callers; nothing touches your event loop if you have one.

• flush(timeout=10.0) forces a send and blocks until it completes.
• Failed batches are retried max_retries times with exponential backoff and jitter, then spilled to a JSONL file in the temp directory. The buffer is keyed to the API key and agent_id, so a restarted process finds its backlog.
• While the backend is down, new events queue behind the buffered ones so delivery order matches production order. Buffered events replay first.
• A repeated failure starts a cooldown between cycles, so a long outage does not cost a full retry budget every flush_interval. An explicit flush() ignores it.
• Permanent failures (400 malformed event, 401 revoked key) are discarded rather than buffered — they would fail identically forever. A revoked key is latched after the first failure, so it fails once, not on a loop.
• An atexit hook flushes whatever is queued at process exit.

Verify your integration

agentaudit.flush()
print(agentaudit.status())
# {'connected': True, 'events_sent': 47, 'events_queued': 0, 'events_buffered': 0,
#  'events_dropped': 0, 'last_flush': '2026-08-18T10:30:00.000Z', 'last_error': None}

events_dropped above zero means audit events were lost — check last_error, raise max_queue_size, or investigate why the backend is unreachable. Then open your AgentAudit dashboard's Timeline — you should see the same events there.

Configuration

agentaudit.init(
    api_key="aa_live_sk_...",
    agent_id="my-agent",
    environment="production",       # -> metadata.environment on every event
    batch_size=50,                  # events per batch (default: 50)
    flush_interval=5.0,             # seconds between flushes (default: 5.0)
    max_queue_size=10_000,          # max events in memory queue (default: 10000)
    timeout=10.0,                   # HTTP timeout in seconds (default: 10.0)
    max_retries=3,                  # retries per batch after the first attempt (default: 3)
    base_url="https://your-agentaudit-backend",  # where your team's backend runs
    debug=False,                    # print debug logs to stderr
    enabled=True,                   # set False to disable without removing code
)

Implemented (0.1.0): init, log_event, set_session, status, flush, shutdown, @trace, LangChainHandler, input/output hashing, event builder, bounded queue, batch sender, offline buffer, retries, atexit hook.