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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds that validation is schema-driven and that the response is a report of populated optional sections, which is useful. It does not disclose whether validation is strict or lenient, what happens to unknown/extra sections, or how failures are surfaced.

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 sentence, front-loaded with the verb and the object, ending with the value proposition. Every clause earns its place 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 read-only, two-parameter tool with no output schema, the description should at least sketch the report's outcome (pass/fail vs. which sections) so an agent knows what it receives. It gestures at that but does not say how validation failures are reported or whether the call always succeeds, leaving a real 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?

Schema description coverage is 100%, so both parameters are already documented in the schema, including the alias list for `descriptor` and the role of `context`. The description adds no syntax, format, or expected-shape detail for the descriptor beyond what the schema provides; baseline 3 applies.

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 (validate), a specific resource (API Onboarding Descriptor / AID), the standard it validates against (api-commons schema), and even the shape of the result (which optional sections are filled). Clear and concrete, but it never names or contrasts itself with the neighbouring validate_api / certify_api tools.

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?

There is no when-to-use guidance at all: no prerequisite that an AID must already exist, no indication of when to prefer this over validate_api or certify_api, and no statement of what a caller should do after a failed validation. The only usage-flavoured text lives in the schema's `context` parameter, not the description.

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