intentgate 0.3.0

Python SDK for the IntentGate authorization gateway

IntentGate Python SDK

The official Python client for the IntentGate authorization gateway.

Companion repositories

Repo	Purpose
intentgate-gateway	Go gateway with the four-check pipeline. The thing this SDK talks to.
intentgate-extractor	Optional FastAPI service that turns user prompts into structured intent.
intentgate-sdk-python	Python SDK for agents (this repo).
intentgate-helm	Helm chart that deploys the gateway, extractor, and Redis to Kubernetes.

What it is

A thin client that lets your AI agent call tools through the IntentGate gateway with a Pythonic API. The SDK handles the JSON-RPC envelope, the Bearer token, the X-Intent-Prompt header, and turns gateway error responses into typed Python exceptions.

Three lines of agent code

from intentgate import Gateway

gw = Gateway(url="http://localhost:8080", token=os.environ["INTENTGATE_TOKEN"])
result = gw.tool_call(
    "read_invoice",
    arguments={"id": "123"},
    intent_prompt="Process today's AP invoices",
)

That's it. Construct once, call as many times as you like. When the gateway blocks the call, tool_call raises a typed exception you can catch.

Install

pip install intentgate

Released versions are published to PyPI on every vX.Y.Z git tag via signed OIDC trusted publishing — see .github/workflows/release.yml.

To install the development tip:

pip install git+https://github.com/NetGnarus/intentgate-sdk-python.git

Exception hierarchy

Every blocked call raises an exception. The class tells you which gateway check fired:

Exception	JSON-RPC code	When
CapabilityError	-32010	Token signature invalid, expired, agent mismatch, tool not in caveat allow-list.
IntentError	-32011	Tool isn't in the intent extracted from the user prompt.
PolicyError	-32012	OPA policy returned deny. The reason carries the Rego rule's explanation.
BudgetError	-32013	A max_calls caveat in the token has been exhausted.
ProtocolError	other JSON-RPC	Malformed request, method not found, etc. Usually means an SDK ↔ gateway version mismatch.
GatewayError	n/a	Couldn't reach the gateway, or got a non-2xx HTTP response.
IntentGateError	(base)	Catch this if you don't care which check fired.

from intentgate import Gateway, PolicyError, BudgetError, IntentGateError

try:
    result = gw.tool_call("transfer_funds", arguments={"amount_eur": 50_000})
except PolicyError as e:
    log.warning("policy blocked: %s (%s)", e.message, e.data)
except BudgetError:
    log.error("agent ran out of budgeted calls")
except IntentGateError as e:
    # everything else: re-raise or surface to user
    raise

API reference

Gateway(url, token=None, *, timeout=10.0, client=None)

Construct a client.

• url — base URL of the gateway, e.g. http://localhost:8080. Trailing slash is tolerated.
• token — capability token from igctl mint. When None, no Authorization header is sent.
• timeout — per-request timeout in seconds.
• client — pre-configured httpx.Client for advanced use (test injection, custom transports). The SDK only closes the client it created itself.

Gateway is also a context manager:

with Gateway(url="...", token="...") as gw:
    gw.tool_call(...)
# client closed automatically

Gateway.tool_call(tool, arguments=None, *, intent_prompt=None, request_id=None) -> ToolCallResult

Invoke a tool through the gateway.

• tool — tool name like "read_invoice". Required.
• arguments — pass-through dict to the tool. The gateway logs only the keys, never the values.
• intent_prompt — the user's natural-language request. Sent as the X-Intent-Prompt header. Strongly recommended in production; without it the intent check is skipped (or denies in strict mode).
• request_id — JSON-RPC id. Defaults to a per-Gateway sequential integer.

Returns a ToolCallResult with:

• content: list[ContentBlock] — what the upstream tool returned (MCP shape, currently type="text" only).
• is_error: bool — MCP-level "tool reported an error" flag (distinct from gateway-level errors that raise exceptions).
• intentgate: IntentGateMetadata | None — gateway decision summary (decision, reason, check, latency_ms).

Typical usage in an agent

The pitch's "three lines" referred to the SDK setup. In practice an agent wraps each tool through the gateway:

from intentgate import Gateway

class FinanceAgent:
    def __init__(self, gateway_url: str, token: str, prompt: str) -> None:
        self.gw = Gateway(url=gateway_url, token=token)
        self.prompt = prompt

    def read_invoice(self, invoice_id: str) -> str:
        result = self.gw.tool_call(
            "read_invoice",
            arguments={"id": invoice_id},
            intent_prompt=self.prompt,
        )
        return result.content[0].text

    def transfer_funds(self, amount_eur: int, recipient: str) -> None:
        self.gw.tool_call(
            "transfer_funds",
            arguments={"amount_eur": amount_eur, "recipient": recipient},
            intent_prompt=self.prompt,
        )

Develop locally

make install     # creates .venv, installs -e ".[dev]"
make lint        # ruff check + ruff format --check
make lint-fix    # auto-fix lint + format
make test        # pytest
make build       # sdist + wheel into dist/ (sanity check before tagging a release)

Tests use respx to mock httpx at the transport level — no real network required, no running gateway needed.

Project layout

src/intentgate/
  __init__.py         # public API: Gateway, exceptions, dataclasses
  client.py           # Gateway client + ToolCallResult dataclasses
  exceptions.py       # IntentGateError hierarchy (CapabilityError, IntentError, ...)
tests/
  test_client.py      # respx-mocked HTTP behavior
.github/workflows/    # CI (lint + tests across Python 3.10–3.13) and release (publish to PyPI on tag)
Makefile              # install / lint / lint-fix / test / build / clean
pyproject.toml        # hatchling build, ruff config, pytest config

Versioning

Pre-release. The wire protocol with the gateway is stable (JSON-RPC 2.0 + the IntentGate-specific error codes), but the Python API surface may change before 1.0.0. Pin to a minor version when integrating.

Contributing

Apache 2.0 and welcomes community contributions. A formal CONTRIBUTING.md is coming with the v0.1 → v1.0 polish pass. For now, please open an issue to discuss any non-trivial change before sending a PR.

Security

If you find a security vulnerability, please do not open a public issue. Email [e-mail] (or open a GitHub Security Advisory on this repo) and we'll respond within two business days.