Harness Capsules Skill

cotcodec / harness/capsules

Purpose

Capsules package declared orchestration inputs, memory graphs, receipts, and verification metadata so an execution can be checked outside its source runtime.

Mental model & key files

• schema.py defines the wire contract.
• runtime.py executes admitted capsule operations.
• verification.py validates hashes, signatures, and declared capabilities.
• memory_graph.py handles capsule-local memory topology.

Patterns to follow / invariants

• Fail closed on unknown fields, algorithms, identities, capabilities, or hashes.
• Bind every decision to canonical serialized bytes and explicit versioning.
• Treat capsules as instrumentation after a real agent loop exists, not as a universal orchestration protocol or a scientific result by themselves.

Common tasks → first action

• Schema change: add a new version plus conformance/tamper vectors.
• Runtime change: update capability declarations and negative verification tests.
• Evidence export: run capsule conformance before referencing the artifact.

Gotchas

• Never accept a trust key shipped inside the artifact it authenticates.
• Hash-valid structure does not establish semantic correctness or model quality.