cicero: Instructions file for Codex

Agent guidance

This is the canonical project guidance for every coding agent. Provider-specific instruction files should import this file instead of copying it.

Product boundary

Cicero is a self-hosted voice layer for coding agents. Keep the voice, transport, and lifecycle code independent of a specific brain. A brain is currently pluggable through the internal TypeScript Brain contract, ACP, an OpenAI-compatible endpoint, or a supported CLI adapter; do not describe the private package as a stable third-party plugin SDK.

The default deployment is single-operator. Do not accidentally turn shared brain state, lanes, or transports into a multi-tenant contract.

Toolchain

• Use the Bun version pinned by packageManager in package.json and CI.
• Use bun install, bun run <script>, bun test, and bun x; do not add a second JavaScript package manager or lockfile.
• Bun is the runtime, but existing node:* standard-library imports are valid.
• Keep dependencies pinned or bounded consistently with the existing lockfile.
• Do not add dotenv; Bun loads environment files itself.

Verification

• Add focused bun:test regressions for behavior changes and run them first.
• Before a PR is ready, run bun run typecheck, the full bun test, and git diff --check.
• tests/brain-claude-code-stream.test.ts is a live smoke test. It runs only with CICERO_LIVE_TESTS=1; never make normal CI depend on installed or authenticated agent CLIs.
• If Python sidecars change, run their matching unittest/native-contract checks with the Python and requirements files used by CI.
• Hardware, credentials, acoustic behavior, and real remote providers need a labeled smoke test; do not present mocked CI as proof of those conditions.

Reliability and security invariants

• Every spawned process, timer, stream, socket, and signal handler needs one owner and a bounded cleanup path. Do not use process-wide kill patterns.
• Put absolute deadlines and size limits around subprocess, HTTP, and streaming work. A timeout must release or quarantine the owned resource before reuse.
• Fail closed when release is unconfirmed, but make stored failure latches retryable so recovery does not require a daemon restart.
• Preserve cancellation, one-shot context, and optional capabilities through every brain wrapper. Late work from an aborted or superseded turn must not publish output into a newer turn.
• Treat config, terminal output, provider bodies, model audio, and transport frames as untrusted input. Bound before retaining, parsing, or logging them.
• Never expose API keys, authorization headers, URL credentials, or query tokens in runtime errors, the application logger, or dashboard events. The ephemeral web credential is intentionally written to startup stdout; remember that a supervisor may retain it, and require a stable token for service deployments. Never commit real credentials, real voice-reference audio, or real user transcripts. Clearly synthetic secret markers are expected in redaction regressions.
• Keep local control surfaces authenticated and private storage symlink-safe.