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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's main job is content context. It does add real value by disclosing that results include an official source URL and a 'date we checked it', which signals data provenance and staleness — a trait absent from the annotations. However, it says nothing about return structure, how many documents are supported, or what happens for unknown inputs.

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 sentence, front-loaded with the tool's purpose and then enumerating returned fields efficiently. The field list is dense but each item earns its place as a substitute for the missing output schema; minor stylistic looseness ('what editing the government forbids') but no wasted sentences.

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 and only two simple parameters, the description carries the burden of telling the agent what comes back — and it does so thoroughly by enumerating the spec fields plus provenance metadata. The remaining gap is edge-case behavior (unsupported country/document, default document semantics), which is minor for a read-only lookup.

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 clear descriptions for both 'country' (name or ISO code, examples given) and 'document' (enum-like list of accepted values). The description adds no parameter-level meaning beyond the schema, so the baseline of 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?

The description states a specific resource — official photo rules for one document — and enumerates the concrete contents (print size, pixels at 300/600 dpi, head height, background, glasses, expression, file limits, editing prohibitions, source URL). The phrase 'for one document' implicitly contrasts with list_photo_specs, but neither sibling is named, so the differentiation is inferred rather than stated.

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 only implied: an agent can infer this is the per-document spec lookup, but nothing says when to prefer it over check_photo_requirements or list_photo_specs. There are no exclusions, no prerequisites, and no note on behavior when a country/document combination is unsupported.

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