image_c2pa_sign

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

With no annotations, the description carries the full burden. It discloses the action (signs with BiGapi certificate), cost ($0.01), and supported formats (JPEG/PNG/WebP). However, it does not disclose side effects such as whether the original file is overwritten or if output_path controls that, nor does it mention authentication requirements, idempotency, or error behavior. It adds some transparency but misses critical details for a mutation operation.

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 concise, with three short sentences front-loading the core purpose. It includes necessary constraints (formats, cost) without padding. The structure is efficient, though the cost statement is a bit tacked on. It earns a 4 for being tight and informative.

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 tool with six parameters, no annotations, and no output schema, the description is insufficient. It lacks parameter explanations, return value information, error handling, and prerequisites (e.g., authentication via get_access). While the purpose is clear, the operational details are missing, making it incomplete for an agent to invoke correctly without further schema inspection.

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 only 17% (only generator has a description). The tool description does not explain any of the six parameters, including file (the required one), title, output_path, ai_generated, or idempotency_key. The description only implies the input is a local path, but it does not specify the meaning, constraints, or format for any parameter, leaving the agent to infer from names alone.

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 the verb (embed), the resource (image), and the specific purpose (C2PA Content Credentials, AI-generated marking, EU AI Act Art. 50 compliance). It also names the signing certificate (BiGapi), distinguishing it from related siblings like image_c2pa_verify (verify) and image_ai_label (label).

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?

Provides clear context for when to use: for compliance with EU AI Act Art. 50 by embedding C2PA credentials. However, it does not explicitly mention alternatives or when not to use it, such as when verification is needed (image_c2pa_verify) or when labeling is desired (image_ai_label). No exclusions are stated.

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