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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so safety is covered. The description adds a non-obvious behavioral constraint — that IDs must originate from this lookup — which is genuinely useful context beyond the annotations, though it says nothing about result size or pagination.

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, front-loaded with the action and searchable fields, followed by the critical downstream constraint. No filler.

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?

For a read-only lookup with no output schema, the definition covers what to search on and why the result matters (the ID). The main omission is any indication of what comes back or how 'limit' affects results, but nothing essential for correct invocation is missing.

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 67%; the schema itself documents 'query' as Name/email/phone and 'location_id' as coming from highlevel_list_locations. The description largely restates the query fields and adds no syntax, matching, or partial-match guidance, and says nothing about 'limit'.

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 ('Find contacts in a HighLevel sub-account') plus the searchable fields (name, email, phone), so the agent knows exactly what the tool does. It doesn't explicitly name sibling tools like highlevel_create_prospect, but the scope is unambiguous.

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 workflow rule: always use this to obtain a contact ID before messaging or adding a note, and never send to a self-composed address. This routes the agent from highlevel_send_message/highlevel_add_note into this tool with no inference required.

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