get_image

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

With no annotations, the description carries the burden of behavioral disclosure. It adds useful details beyond the schema: supported formats (PNG/JPEG), return contents (image plus caption/description/page metadata), and a type condition. It doesn't explicitly mention error records, but the schema covers that, and the read-only nature is implied by 'Fetch'.

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?

The description is two focused sentences with no wasted words. The primary action is front-loaded, followed by return details and the critical type limitation. Every sentence 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?

For a single-parameter tool with no output schema, the description is quite complete: it covers input source, behavior, output contents, and the image-only constraint. The only notable omission is an explicit statement of error behavior for non-image refs, but that is already present in the param schema.

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 the baseline is 3. The description reinforces the semantics of 'refs' by echoing 'opaque tokens from search/lookup/get' and mentioning the image-segment constraint, but it does not add meaning substantially beyond what the schema already documents.

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 clearly states a specific verb and resource: 'Fetch datasheet figure images' for opaque ref tokens. It also specifies the output (image plus caption/description/page metadata) and a key constraint ('Only type='image' segments have image data'). While it doesn't explicitly name sibling tools, the image-specific scope and source of refs effectively distinguish it from likely siblings like get_specs or get.

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 description gives clear context for when to use the tool: when you have opaque ref tokens from search/lookup/get and need image data. It also warns that only image-type segments have image data, implying non-image refs are inappropriate. However, it does not explicitly contrast with alternatives or state when to use a different tool.

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