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

Annotations already cover the safety profile (readOnly, non-destructive, openWorld), so the bar is lower; the description still adds ordering ('newest first'), page size (up to 100), cursor round-tripping (pass next_cursor back as cursor), and an auth requirement (Cotlet API key with access). It does not describe rate limits or failure modes, so not a 5.

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 core facts are front-loaded, but the paragraph repeats itself: 'newest first' appears twice and the searchable fields are listed twice ('Search by name, email or tax ID' then 'Search matches name, email or tax ID'). Tightening would remove roughly a third of the text with no loss.

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 4-param, no-output-schema listing tool, the description covers ordering, pagination mechanics, searchable fields, filter vocabulary, and auth. Missing only return-shape detail (what a contact record contains beyond the four named fields), which 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?

With 100% schema coverage the baseline is 3, and the description earns above that by explaining the type vocabulary ('the contact type Holded uses'), what search actually matches (name, email or tax ID), and that cursor comes from the previous page's next_cursor field. These are semantic additions beyond the terse schema descriptions.

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+resource (lists contacts in your Holded account) and enumerates the returned fields (name, type, email, tax ID) plus sort order. It even routes away from the create path ('find a contact before creating one'). It does not differentiate from sibling holded_get_contact, so it falls short of a 5.

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 a concrete when-to-use case: search before creating a contact, which is exactly the pre-write lookup pattern. However it never names holded_get_contact as the alternative when an ID is already known, so there are no explicit exclusions.

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