Bicameral MCP

The agent-facing MCP tool surface for the local Bicameral daemon

⚡ Quick Start · 🧰 Tools · 🔌 Contract · 🏛️ Governance · 🛡️ Trust

bicameral-mcp is the MCP transport client for the local bicameral-bot daemon. It exposes agent-friendly tools, maps them into canonical ToolRequest envelopes, sends those requests to the daemon, and returns daemon ToolResponse payloads.

MCP is not the Bicameral daemon, Decision Ledger, code graph, dashboard, integration runtime, setup wizard, telemetry sink, or governance engine. Edge surfaces propose; the daemon decides what becomes canonical.

Table of Contents

• Current Contract
• Configuration
• Supported Tools
• Product Terminology
• Troubleshooting: Daemon Handshake Failures
• Prompts And Skills
• Retired From MCP
• Development
• Repository boundary
• Governed by the Bicameral Factory
• Trust & Compliance
• Security
• License

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Current Contract

The cutover target is the bot-owned ToolRequest protocol:

MCP tool call
  -> ToolRequest(command + AuthorityContext)
  -> bicameral-bot daemon validation and governance policy
  -> ToolResponse(status + result + governance_result)

MCP performs a daemon capability handshake at startup. It refuses to start when the daemon's ToolRequest protocol version is unsupported. After protocol compatibility is established, individual commands may still return daemon capability errors while bot parity is being implemented.

Configuration

Set the bot daemon endpoint with:

export BICAMERAL_DAEMON_URL=http://127.0.0.1:37373

Optional context:

export BICAMERAL_ACTOR_ID="$(whoami)"
export BICAMERAL_WORKSPACE="$PWD"
export BICAMERAL_POLICY_SCOPE=default

Run the MCP server:

bicameral-mcp

Print supported tool names without contacting the daemon:

bicameral-mcp tools

Supported Tools

MCP exposes only ToolRequest-backed tools:

MCP tool	Bot command
bicameral.ingest	ingest.submit_local
bicameral.capture_context	ingest.submit_local
bicameral.preflight	preflight.run
bicameral.context	lookup.query
bicameral.correction_findings	lookup.query
bicameral.lookup	lookup.query
bicameral.bind	binding.create
bicameral.binding.inspect	binding.inspect
bicameral.evidence.refresh	evidence.refresh
bicameral.review.candidates	search.query
bicameral.review.corpus_proposals	lookup.query
bicameral.review.accept_candidate	review.accept_candidate
bicameral.review.reject_candidate	review.reject_candidate
bicameral.review.promote_candidate	recall.promote_decision_candidate
bicameral.review.request_corpus_change	recall.request_correction
bicameral.review.approve_signoff	review.approve_signoff
bicameral.review.reject_signoff	review.reject_signoff
bicameral.review.resolve_compliance	review.resolve_compliance
bicameral.history	history.list
bicameral.search	search.query
bicameral.review.contradictions	governance.inbox.list
bicameral.review.triage_contradiction	governance.resolve_contradiction
bicameral.governance.inbox	governance.inbox.list
bicameral.governance.inspect	governance.inspect
bicameral.governance.resolve	governance.resolve_contradiction
bicameral.recall.inspect_evidence	recall.inspect_evidence
bicameral.recall.expand_scope	recall.expand_scope
bicameral.request_correction	correction.request

Product Terminology

bicameral.preflight is the MCP surface for constraint lookup and readiness context before or during implementation. It maps to the bot-owned preflight.run command for historical protocol compatibility, but MCP does not turn lookup output into a governed work gate, compliance decision, signoff, or merge-safety claim.

Use these terms consistently:

• Constraint Lookup: retrieve relevant daemon-authored Decisions, source links, evidence references, and readiness labels.
• Constraint Correction Capture: submit or review proposed corpus corrections.
• Code Grounding: inspect daemon-owned binding and graph evidence.
• Code Compliance: review daemon-owned compliance state when the daemon exposes that capability.
• Governed Work Gate: future policy-controlled blocking/routing behavior; not implied by ordinary lookup or preflight output.

Troubleshooting: Daemon Handshake Failures

MCP stays fail-fast on daemon capability handshake failures. It never starts, installs, upgrades, migrates, or repairs the daemon, and never falls back to legacy MCP-owned handlers. Instead, a failed tool call returns a typed MCP error with an informational recovery payload:

{
  "status": "error",
  "error_code": "daemon_protocol_mismatch",
  "recovery": {
    "error_code": "daemon_protocol_mismatch",
    "category": "setup",
    "retryable": false,
    "mcp_protocol_version": "v2",
    "daemon_protocol_version": "v1",
    "daemon_endpoint": "http://127.0.0.1:37373",
    "requested_tool": "bicameral.preflight",
    "requested_command": "preflight.run",
    "operator_action": "Upgrade bicameral-mcp and bicameral-bot/daemon to matching tags, then retry."
  }
}

error_code	Meaning	What to do
daemon_unavailable	MCP cannot reach the configured/local bot daemon.	Start or install the Bicameral bot daemon, then retry.
daemon_protocol_mismatch	Daemon is reachable but its ToolRequest protocol version is incompatible.	Upgrade bicameral-mcp and bicameral-bot/daemon to matching tags, then retry.
daemon_capability_error	Daemon answered capabilities but the requested command is unadvertised or deferred.	Use a supported command, or upgrade to a daemon tag that advertises the capability.
Wrong daemon URL	Connection target is misconfigured via an env override.	Unset or correct BICAMERAL_DAEMON_URL / BICAMERAL_BOT_DAEMON_URL, then retry.

When a daemon URL env override is set, the recovery payload adds a daemon_url_override field and calls out the env var in operator_action, so a wrong URL is easy to spot even though it shares the daemon_unavailable transport path.

Remediation such as installing, upgrading, starting, or migrating the daemon is bot-owned or CLI-owned, not MCP-owned.

Prompts And Skills

MCP may expose MCP prompts for generic Bicameral workflows over supported tools, such as constraint lookup, binding, ingest, history, search, and brief.

Repo-local skills are outside MCP. Keep repo/team behavior in repo skills: when to run Bicameral, which ADRs to read, contribution policy, factory attestation, and workflows that span beyond Bicameral MCP.

Retired From MCP

The v0.2 direct MCP payload surface is not preserved. Removed or unsupported legacy behavior includes:

• link_commit
• ratify
• resolve_collision
• remove_decision
• remove_source
• validate_symbols
• get_neighbors
• setup wizard, reset, update, diagnose, usage, feedback, and telemetry
• dashboard hosting
• local ledger/event/graph/source/integration runtimes

Missing bot-backed behavior is intentionally unavailable in MCP rather than emulated locally.

Previous implementation history can be inspected at:

0827444c80d45fe3474f68002166e1fc35708eda

Development

Focused cutover checks:

python -m pytest tests/test_toolrequest_thin_client.py -q
python -m build

Repository boundary

bicameral-mcp is the agent-facing tool surface. It exposes local Bicameral actions to coding agents: ingest, preflight, bind, review-command emission, and local run loops.

It is not the source-specific integration repo, the local bot runtime, or the hosted code graph. See docs/adr/0001-mcp-repository-boundary.md.

Governed by the Bicameral Factory

This repository is part of the BicameralAI organization and is governed by the Bicameral Factory, the org's governance control plane. The factory aggregates each repo's declared governance facts (classification, visibility, required checks) into an org-wide governance dashboard. Governance is evidence-first: status is read from hard evidence such as CI runs, file presence, and branch protection, never inferred.

Trust & Compliance

BicameralAI is pursuing SOC 2 Type II and ISO 27001. Framework-level status and evidence are available through our Vanta Trust Center; access to detailed reports is provided under a non-disclosure agreement. This summary is framework-level by design; detailed control and test posture is maintained internally and is not published here.

Security

Please report security issues to security@bicameral-ai.com. Do not open a public issue for a suspected vulnerability. See SECURITY.md for the full policy, coordinated-disclosure timeline, and safe-harbor terms.

License

Bicameral MCP is licensed under the Business Source License 1.1 (BSL 1.1). You may copy, modify, and make non-production use freely; production use is permitted except for offering the software as a hosted or embedded service that competes with BicameralAI's paid offerings, including Bicameral Cloud. Each released version converts to the Apache License 2.0 on its Change Date, four years after that version's release. For commercial or alternative licensing, contact licensing@bicameral-ai.com.