Agent = Model + Harness.
Everyone has access to the same models. The harness is where reliability is engineered. Synapse is a reference implementation of Harness Engineering — the 2026 engineering discipline for production AI teams.
Guides and Sensors
A harness is two things working together. Guides are feed-forward: they shape behavior before action — the CLAUDE.md persona, the organization.yaml routing table, the decision_rules.yaml constraints, the agent capability cards.
Sensors are feedback: they watch behavior after action — the 85/100 QA review, the execution-chain auditor, the decision log, the cross-session state file.
Guides stop drift. Sensors catch it when it happens anyway.
The execution chain
Five steps, every time. Violating any one of them is logged as a P0 break.
Greeting + objective intake.
Lysander confirms identity and restates the goal.
Classification.
The execution_auditor grades the task S/M/L. S ships fast. L goes through expert review.
Mandatory dispatch table.
No work starts without a named specialist and a named deliverable. This is a hard constraint.
Isolated execution.
Specialists run in sub-agent contexts. The CEO persona never touches Edit/Write/Bash directly — CEO Guard blocks it.
QA gate + delivery.
integration_qa scores the output on integrity, accuracy, consistency, maintainability, compliance. ≥85 ships.
The three-layer CLAUDE.md
Synapse's CLAUDE.md is three layers with distinct cache lifetimes.
- Layer 1 Identity (~25 lines) — changes almost never.
- Layer 2 Harness rules (~170 lines) — changes on upgrades.
- Layer 3 Instance config (~85 lines) — changes on personalization.
The ordering is deliberate: stable content first so the Anthropic prompt cache stays valid across turns, cutting cost by ~90% on hits.
Entropy budget
Every rule in Synapse carries a timestamp. Every 3 days, harness_engineer runs audit_harness() against the CLAUDE.md file — line count, duplicate semantics, stale rules past 180 days.
Above 300 lines, new additions are blocked until something is removed. Governance is a first-class feature, not an afterthought.
Ready to run it yourself?
Download the configuration bundle. Clone, swap three variables in CLAUDE.md, restart your Claude Code session — and the first dispatch can run.