v1.5.0 - Runtime Process Guard

Highlights

• Runs MCP stdio servers in a disposable working directory by default.
• Passes only a minimal environment allowlist unless explicitly configured otherwise.
• Enforces combined stdout/stderr byte limits and JSON-RPC message limits.
• Uses bounded binary readers with strict UTF-8 and line-delimited JSON validation.
• Redacts JSON-RPC error objects and records only a non-sensitive runtime policy summary.
• Adds POSIX process-group cleanup and fail-closed handling for late output floods.

New CLI controls

• --runtime-cwd PATH
• --runtime-allow-env NAME
• --runtime-inherit-env
• --runtime-max-output BYTES
• --runtime-max-messages COUNT

Verification

• 45 unit and regression tests
• Benign precision gate: 0 enforce findings
• Malicious recall gate: expected finding exit code
• Wheel and sdist build
• Installed-wheel CLI and rule discovery smoke test

Security boundary

The runtime guard reduces environment leakage, working-directory coupling, and output resource exhaustion. It is not an operating-system sandbox and does not block absolute-path file access or network connections.

v1.4.1 - Runtime trust hardening

Highlights

• Harden MCP stdio runtime probing with strict JSON-RPC and initialize response validation.
• Redact server command arguments and tool metadata from runtime reports.
• Fix source locations for Unicode, JSON escapes, and matching key/value names.
• Detect malicious payloads nested in bounded, double-encoded Base64.

Verification

• Python 3.10-3.13 CI matrix
• 37 unit and regression tests
• Benign precision gate and malicious recall gate
• Python package build verification

See CHANGELOG.md for the full release history.