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

readOnlyHint=true already establishes this as a safe read, so the bar is lower. The description adds useful behavioral context by naming cursor pagination and the page_size/page_token mechanism, but says nothing about rate limits, result caps, or what a response contains (e.g., next_page_token), which matters for a paginated listing call.

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-loaded with what the tool does before capability detail. Every clause carries information and nothing is redundant.

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 list tool with full schema coverage and no output schema, the description covers purpose, capabilities, and pagination – enough for an agent to call it correctly. It could be strengthened by hinting at the pagination response cursor, but nothing essential 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 description coverage is 100%, so the schema already documents all five parameters with examples (filter expression syntax, order_by negation, max page size). The description only restates the same categories (filtering, ordering, field selection, pagination) without adding syntax or format detail beyond the schema. Baseline 3 is correct here.

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 states a specific verb and resource ('List contacts in the Keap CRM') and even names the backing endpoint (GET /contacts), so the agent knows exactly what operation is performed. It is clearly separable from siblings like keap_get_contact or keap_create_contact by the verb alone, though it never explicitly differentiates itself from them.

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?

It lists the capabilities (filtering, ordering, field selection, pagination) which implies browsing/searching use cases, but gives no explicit when-to-use versus when to use keap_get_contact or a filtered list instead. Usage is inferable rather than stated.

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