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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds real behavioral context beyond that: it is a lookup that reports scope/role requirements and 'whether this connection may call it', i.e. it performs a permission check rather than any API call. It stops short of mentioning errors, rate limits, or caching.

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?

A single front-loaded sentence: purpose first, then the enumerated return contents. The enumeration is dense but everything listed is useful for a tool with no output schema. The 30+ word tail is long for one sentence but not padded with 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?

With no output schema, the description carries the burden of describing the response, and it does so thoroughly: method, path, summary, description, path/query parameters, request-body rules, an example body, required scope and role permissions, pagination notes, and callability for this connection. Nothing an agent needs before invoking it 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 coverage is 100% and the schema already provides the example value 'post.inventory-adjustments', so the baseline is 3. The description adds provenance the schema lacks - the id must come from search_api - which is genuine extra meaning for the caller.

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 and resource ('Describes one SKU.io REST API endpoint') and names the exact key it operates on ('by its endpoint_id'). It also ties itself to the sibling that supplies that key ('from search_api'), letting an agent distinguish it from search_api and the api_read/api_write family without opening a schema.

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 phrase 'by its endpoint_id from search_api' establishes the workflow: first find endpoints, then describe one. However, it never explicitly states when to use this instead of the raw api_read/api_write tools or what to do when endpoint_id is unknown; the routing is implied rather than spelled out.

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