Understand the records behind context.

Delivery is not retention

A read representation describes what an operation returned. A session record describes retained work state. A knowledge export describes selected facts. A receipt links an operation to evidence about its result.

Choose the record that answers your question instead of treating every artifact as a full transcript.

MCP and the Engine interface

MCP exposes named tools and JSON input schemas to a host. The local Engine interfaces used by the SDK are separately versioned transports with explicit negotiation.

A callable MCP name is not necessarily an SDK method. A new runtime version is not automatically compatible with a pinned SDK release.

Recoverable representations

Compact output can carry a reference to retained source or archived output. Recovery requests must use the correct handle and remain subject to availability and policy.

A lossless format transformation and a lossy summary with a recovery path are different contracts. Verify which one produced your result.

Portable knowledge

Open Knowledge Format uses Markdown records with metadata and relationships. Native JSON and context packages have different envelopes and import behavior. Review contents before moving them between projects.

Draft specifications

Older OCP (Open Context Protocol) and CGB (Context Graph Bundle) pages described protocol directions. They are not an additional stable integration surface. Use the versioned SDK public manifest, MCP schemas or documented export format that actually serves your workflow.

Do not infer wire compatibility, certification or a supported importer from a draft name. Review feature and version boundaries before building against a specification.

Evidence and verification

Receipt linkage or signature verification checks particular integrity properties. It does not establish task success, legal compliance, trustworthy authorship or provider invoice savings on its own.

Use observability to connect an operation, its delivered content and the outcome you actually measured.

Sources & versions4 references · Reviewed 17 Sept 2026

• 03-memory-and-knowledge.mddocs/reference/03-memory-and-knowledge.mdGitHub
• mcp_manifest.rsrust/src/core/mcp_manifest.rsGitHub
• PUBLIC-SURFACE-MANIFEST.mdSDK / PUBLIC-SURFACE-MANIFEST.mdGitHub
• COMPATIBILITY.mdSDK / COMPATIBILITY.mdGitHub

Core checkout

0ce2207ee4

Installed runtime

3.10.2

SDK release

1.1.0

Separate baselines for source, CLI/configuration and SDK contracts. Review does not certify every platform or integration.

Versions & compatibility