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 bar is lower. The description still adds real value with 'The server returns URLs, not image bytes', which prevents an agent from expecting binary content, and by enumerating the response fields in the absence of an output schema.

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?

Two tight sentences with zero filler; the resource and field list come first, followed by the one operational caveat. Every clause earns its place.

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 no annotation detail on returns, the description appropriately enumerates what comes back and clarifies URLs vs. bytes. The remaining gap is provenance of image_id and error behavior, which an agent would want for a required single-parameter 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 0% and the single parameter (image_id, integer) is undocumented in the schema, so the description must carry the load. It says only 'by id' and never states the id format, its source (e.g. from a search result), or behavior for an unknown id.

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 ('Get') and resource ('one photograph by id') and enumerates the returned fields (title, photographer, capture date, coordinates, subjects, rights, IIIF manifest, image_url). It is clearly a single-record fetch, which implicitly separates it from search_images/semantic_search_images, but no sibling is named explicitly.

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 id' implies this is the tool to call once you already have an image_id, but it never says so outright or points to search_images/semantic_search_images as the way to obtain one. No when-not-to-use guidance is given.

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