Update a media asset

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

Adds meaningful behavioral context beyond annotations: changing site content, non-publication, immutable bytes, and required secret key with media:write scope. No contradiction with annotations.

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?

Concise, front-loaded single paragraph with each sentence adding distinct information: editability, immutability, publishing separation, and auth requirements.

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?

Despite no output schema, the description covers purpose, constraints, auth, and alternatives, making the tool's behavior fully understandable for selection and 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 covers all parameters (id, alt_text, if_match) with detailed descriptions, so description adds little beyond reinforcing that only alt_text is editable. Baseline 3 applies due to high schema coverage.

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?

Clearly states the tool updates a media asset and specifically limits editing to alt_text. This distinguishes it from siblings like upload_media (for creating/replacing) and delete_media (for removal).

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?

Explicitly says bytes are immutable and to replace an image, upload a new one and repoint references, pointing to a different workflow. Also states publishing is a separate call, guiding when not to use this tool for publication.

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