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

Annotations only provide readOnlyHint=true; the description adds meaningful behavioral context by disclosing supported query capabilities (filtering, ordering, field selection) and cursor pagination with page_size/page_token. Matching the GET /contacts method reinforces the read-only nature without contradicting annotations.

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 compact sentences front-load the purpose and capability list, then close with the endpoint. No filler or redundant restatement of parameter names.

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 list operation with no required parameters and a fully documented schema, the description covers the important calling context: it identifies the resource, supported query features, and pagination mechanism. It does not describe the response envelope, but the schema's page_token explanation references next_page_token, and the endpoint is simple enough that this is a minor gap.

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?

All 5 parameters are already described in the input schema (100% coverage), so the schema carries the semantic burden. The description's brief mention of filtering/ordering/field selection/pagination aligns with the parameters but adds little detail beyond what the property descriptions already say.

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 a specific verb ('List') and resource ('contacts in the Keap CRM'), and reinforces the operation with the actual endpoint 'Keap: GET /contacts'. The plural resource and listing verb differentiate it from sibling get_contact/single-object tools.

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?

Implied usage is clear: use this when you need to enumerate or search contacts in Keap rather than fetch a single contact or list a different entity. However, it does not explicitly state when to choose this over alternatives (e.g., get_contact for one record) or any exclusions.

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