MACP Capability Registry

This registry defines standard capability identifiers used by MACP agents and runtimes.

Format

Capability identifiers use the pattern:

macp.<category>.<name>.v<version>

Example:

macp.signal.v1 macp.mode.decision.v1 macp.transport.grpc.v1

Standard Capabilities

Capability Registry vs. Capability Objects

The Capability Registry (this document) lists high-level feature identifiers used in agent manifests and discovery endpoints (see RFC-MACP-0005). These identifiers follow the macp.<category>.<name>.v<version> pattern and declare what an agent or runtime supports at the advertisement level.

The Capability Objects defined in RFC-MACP-0001 Section 4.2 are structured protobuf fields (e.g., sessions.stream, cancellation.cancelSession) exchanged during InitializeRequest/InitializeResponse negotiation. These represent fine-grained feature toggles negotiated at connection time.

Both systems serve complementary purposes:

• Registry identifiers appear in manifests and discovery responses to advertise broad capabilities before a connection is established.
• Protobuf capability fields are exchanged during the Initialize handshake to negotiate specific features for a given connection.

Extension Policy

New capabilities may be registered through:

• MACP working group review
• documented community proposal
• experimental namespace

Example experimental identifier:

com.example.capability.custom.v1