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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds meaningful value beyond them by disclosing the shape of the result set (the specific fields returned), which matters because there is no output schema. It stops short of describing filtering, ordering, or pagination behavior.

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?

One tight sentence with the action and scope front-loaded, followed by the field list. Every token carries information and there is no 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?

For a one-parameter, read-only list tool with no output schema, near-complete: the return fields are enumerated and the safety profile is covered by annotations. The only gap is the absence of any note on scope (single site vs all sites) or ordering of results.

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% and the single site_id parameter is fully documented in the schema ('Site id. Pass it on every call.'). The description adds nothing further about the parameter, so the baseline 3 for a schema-documented parameter set is appropriate.

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 gives a specific verb ('List') and resource ('the site's collections'), and clarifies the domain as 'headless CMS' so the resource isn't confused with pages, nodes, or templates. It also enumerates the returned fields (id, name, slug, row and field counts, public flag), which further pins down what this tool is versus get_collection or list_collection_rows.

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 resource — you call this to enumerate collections on a site — but there is no explicit statement of when to prefer it over get_collection (single item) or list_collection_rows (rows within a collection). No exclusions or prerequisites are stated.

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