vision_annotate

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

No annotations are provided, so the description carries the full burden and does not meet it. It discloses only that output is 'structured JSON'; it says nothing about whether the operation is read-only, which of the three image inputs (image_url / image_path / image_base64) is required or takes precedence, model/latency implications, or any failure modes.

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 with no filler. The parenthetical enumeration is dense but every item earns its place by scoping what counts as an 'annotation'.

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 should say more about the 'structured JSON' it returns (shape/fields), and it never resolves the ambiguity of six optional params offering three alternate image inputs with nothing marked required. Adequate for a first-order call, but incomplete for reliable invocation.

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 schema already documents all six parameters including the model default and the MIME/Base64 pairing. The description adds nothing about parameters, so the baseline 3 applies — it neither compensates for nor undermines the schema.

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 ('Identify') and resource ('user's visual annotations') and enumerates the annotation kinds (circles, arrows, underlines, highlights, scribbles, handwritten text) plus 'their targets'. This is clearly distinct from vision_ocr or vision_layout in practice, but no sibling is named, so differentiation is implicit rather than explicit.

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, no stated preconditions, and no mention of when to prefer this over vision_ocr (which also handles handwritten text), vision_inspect, or vision_layout. Usage must be inferred entirely from the tool name and the enumeration of annotation types.

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