agentassert-typec-core

Formal behavioral contract kernel. Provider-blind, transport-blind.

This is the core engine — zero LLM deps, zero HTTP deps. Every adapter (proxy, SDK, hook) imports this.

Features

• 7 Process Contract Operators — tool_blocklist, tool_allowlist, must_state, must_precede, context_budget, process_drift, judge_predicate
• ContractSpec DSL — YAML-based, dsl_version: "0.4" for full Type-C, dsl_version: "0.3" for ABC compatibility
• JSD Drift Tracker — Welford-style incremental (O(1) per update), frozen baseline at window boundary
• Θ Reliability Scorer — Θ = 0.35C̄ + 0.25(1-D̄) + 0.20/(1+E) + 0.20S
• Thread-safe SessionMonitor — RLock-protected, evaluate() never blocks for >10ms
• Pre-compiled AST — all regex patterns compiled once at SessionStart

Install

pip install agentassert-typec-core

Quickstart

from agentassert_typec_core import SessionMonitor, PreAction, DecisionResult

monitor = SessionMonitor.from_yaml("contract.yaml")
event = PreAction(session_id="s1", contract_id="c1", tool="Read", args={})
result = monitor.evaluate(event)
print(result.decision.name)  # ALLOW or DENY

Optional: OTel

pip install agentassert-typec-core[otel]

License

MIT