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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds meaningful context beyond that: the upstream endpoint, the supported query surface, and crucially the response envelope shape { meta, response }, which the agent would otherwise not know since there is no output schema.

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?

Three short fragments, zero filler, and the most important information (what it lists, the endpoint, the query surface, the return shape) is front-loaded. Every clause earns its place.

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?

There is no output schema, but the description compensates by naming the { meta, response } envelope and summarizing pagination/filter support. Combined with 100% schema coverage, an agent has enough to call this correctly, though ordering/pagination defaults could be stated more explicitly.

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 fully documents all five parameters, including filter syntax examples. The description's mention of _page/_limit/_fields/_filters/_search only repeats parameter names without adding format or interaction detail, so the baseline 3 applies.

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 ("List contacts (people at companies)") and even names the underlying API call GET /api/v0/contacts. The parenthetical disambiguates the resource nicely, though it doesn't explicitly contrast with get_contact or list_companies beyond the list/get naming distinction.

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?

Usage is implied by the verb and the enumerated query capabilities (_page/_limit/_fields/_filters/_search), so the agent can infer this is the bulk-retrieval tool. However, there is no explicit when-to-use guidance, no statement of when to prefer get_contact, and no exclusion conditions.

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