External AI Ecosystem Gateway

A security-oriented Python gateway that exposes permission-scoped tools to MCP-compatible assistant clients while mediating access to external systems such as Slack. It demonstrates tenant isolation, delegated authorization, human confirmation for sensitive writes, idempotent execution, signed webhook verification, revocation-ready grant storage, and a hash-chained audit trail.

This is a portfolio/reference implementation, not a production identity provider. The header-based development auth adapter must be replaced by the OIDC validation middleware described in docs/security.md before deployment.

Architecture

Assistant / Slack client
          |
          v
  FastAPI edge + auth adapter
          |
          v
 Policy + tenant boundary ----> confirmation tokens
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          v
 Sandboxed tool registry -----> Slack / OpenAI / Claude adapters
          |
          +--------------------> idempotency store
          +--------------------> append-only hash-chained audit log

Quick start

python -m venv .venv
source .venv/bin/activate
pip install -e '.[dev]'
uvicorn ecosystem_gateway.app:app --reload

List tools:

curl localhost:8000/mcp/tools \
  -H 'X-Subject: user-1' -H 'X-Tenant-Id: tenant-a' -H 'X-Roles: operator'

Run the test suite with pytest. When no Slack token is configured, connectors run in a safe sandbox mode and return the request they would issue.

Security properties

• Every principal and idempotency key is tenant-namespaced.
• Tool policies combine least-privilege roles with delegated scopes.
• Sensitive writes require a short-lived token bound to subject, tenant, tool, and arguments.
• Webhook signatures use constant-time comparison and reject stale requests.
• Audit records form a SHA-256 chain so deletion or mutation is detectable.
• OAuth grants support revocation and never expose refresh tokens through tool results.

See docs/security.md for the production hardening checklist and threat model.

License

MIT