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

Annotations already declare readOnlyHint=true, so the agent knows this is a safe read operation. The description adds the REST endpoint (GET /rest/companies) and capability notes (pagination, filter, depth), but does not disclose additional behavioral traits such as return format, pagination loop behavior, or any side effects. Given the annotation coverage, this is adequate but not rich.

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?

The description is three short sentences, front-loaded with the primary purpose. Every sentence adds value: stating the function, noting key capabilities, and providing the underlying REST endpoint. There is zero redundancy or 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?

Given the moderate complexity (6 parameters, all well-documented in schema) and the presence of readOnlyHint, the description is sufficiently complete. It conveys the endpoint, core capabilities, and purpose. Lacking an output schema, it doesn't describe the response shape, but for a list tool this is not a critical omission. The schema covers parameter behavior, and the annotations cover safety.

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%, with detailed descriptions for all 6 parameters including examples, syntax, and comparators. The description only mentions 'raw filter/order_by, and relation depth' generically, adding no value beyond the schema. The baseline of 3 is appropriate because the schema already does the heavy lifting.

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 opens with 'List/filter companies', a specific verb+resource combination that clearly states the tool's function. It distinguishes itself from sibling tools like twenty_get_company (single record) and twenty_create_company (write operation) by explicitly mentioning list/filter and pagination/filtering capabilities.

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?

The description provides clear context for when to use this tool by highlighting its unique capabilities (cursor pagination, raw filter/order_by, relation depth) absent from other sibling tools. It implies this is the tool for listing/filtering multiple companies, though it doesn't explicitly state exclusions or alternatives like 'Use get_company for a single record.'

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