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

Annotations declare readOnlyHint=true, so no need to restate. Description adds context that it's a GET endpoint and can search by various fields. No contradictions. Could mention pagination behavior more explicitly, but adequate.

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?

Two sentences: first sets purpose, second gives usage guidance. No redundant words. Front-loaded and efficient.

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 10 parameters and no output schema, the description covers the core use cases. It could mention that the response is a list of entities and hint at pagination via startingAfter, but the schema descriptions handle parameter details. Sufficient for a straightforward read-only search 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 description coverage is 100%, so the schema already documents all parameters. Description adds value by grouping searchable fields (name/email/foreignId) but doesn't significantly enhance understanding beyond schema.

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?

Clearly states verb (find/search) and resource (entities), and distinguishes by specifying counterparty types (buyers, vendors, payors, payees). Differentiates from sibling tools like create_entity or get_entity.

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?

Explicitly instructs to use for looking up counterparties by name/email/foreignId or listing all entities. However, it does not mention when to use get_entity instead (e.g., when you need a single entity by ID) or specify exclusions.

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