Relay Registry Search

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint and openWorldHint, and the description reinforces that with 'read-only, server-side' and 'never touches the Client and never writes any configuration'. It adds real value beyond annotations by disclosing pagination behavior (next_cursor) and that a returned name is the 'source' for adding a server. It stops short of full disclosure, but it is well above the annotation-provided baseline.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads purpose, then routing, then return shape and safety in four compact sentences. Slightly dense but every sentence carries information an agent needs; nothing is wasted.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, the description needn't enumerate return fields, yet it still summarizes the returned metadata and the cursor contract. Combined with annotations and full schema coverage, an agent has everything needed to invoke and chain this tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so all six parameters are already documented in the schema, including limit, cursor, version, updated_since and include_deleted. The description mentions only the cursor/next_cursor handoff, which the schema already states. Baseline 3 is correct when the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Search the official MCP Registry for servers') plus scope ('to add'). It explicitly distinguishes itself from the sibling relay_status for already-configured servers, so an agent can route without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives an explicit when-to-use ('discover a server that is not configured yet') and names the alternative (relay_status) with its own condition ('for the servers the Client already runs'). Nothing is left to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.