search_external_marketplaces

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

Annotations already declare readOnlyHint, destructiveHint, and idempotentHint, indicating safe read operation. The description adds value by listing specific actions it does not perform (e.g., 'does not call, execute, submit'), which provides extra behavioral clarity beyond what annotations offer. No contradictions are present.

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?

The description is extremely concise, consisting of two sentences. The first sentence delivers the core purpose, and the second sentence lists exclusions without unnecessary detail. Every word serves a purpose, making it efficient and easy to parse.

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?

Given the tool's simplicity and high schema coverage, the description is adequate but lacks information about the return format or behavior. It does not mention that the tool returns a list of candidates or how results are structured, which would be helpful for an agent invoking it without an output schema.

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?

The input schema has 100% description coverage, so all 9 parameters are already documented with clear definitions. The description does not add any parameter-specific semantics beyond what the schema provides, earning a baseline score of 3.

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?

The description clearly states the verb 'Search' and the resource 'local public-safe external marketplace supply metadata', which is specific and distinguishes it from siblings like 'list_external_supply_sources' or 'explain_external_marketplace_boundaries'. The negative list further clarifies what the tool does not do, reinforcing its read-only nature.

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?

The description implies a read-only usage context through the negative list, but it does not explicitly state when to use this tool versus alternatives like 'agoragentic_search' or 'inspect_external_supply_candidate'. No comparison or exclusion criteria are provided, so the agent must infer usage from the tool's name and description alone.

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