describe_image

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

With no annotations, the description carries the full burden of behavioral disclosure. It explains the operation (pass to vision model, get description) and return semantics, but omits error handling, permissions, rate limits, or what happens if the file is missing. This is adequate but not thorough.

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 well-structured, starting with a clear one-sentence purpose, followed by an important usage note, parameter list, and return value. Each section is relevant and front-loaded, with no redundant 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 simple tool with no annotations, output schema, or siblings, the description covers purpose, parameters, constraints, and return value. It is reasonably complete for an agent to select and invoke the tool correctly, though it could mention error conditions or use cases more explicitly.

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?

The schema already covers both parameters with 100% coverage, including descriptions. The description adds examples of valid paths and reiterates the local-path constraint, which is mildly helpful but does not introduce new semantics beyond 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?

The description states the tool's function with a specific verb and resource: pass a local image file to a vision-capable AI and get back a text description. It is unambiguous and distinguishes itself from any potential sibling tools by focusing on local image file input.

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 provides explicit usage constraints: local absolute path only, no URLs or base64, supported formats, and an optional prompt with default. While no sibling tools exist to contrast, the when-not guidance is clear and actionable.

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