update_pixel

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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It only states 'update an existing retargeting pixel' and does not explain whether updates are partial or full, whether any fields are required beyond id, what happens to unspecified fields, or the nature of the response. This is insufficient for a mutation tool.

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 a single, concise sentence that is front-loaded with the core action and resource. It contains no unnecessary words or redundant information, earning a top score for conciseness.

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?

This is a simple update tool, but with no output schema and no annotations, the description provides no information about return values, side effects, or error conditions. The agent is left to assume standard behavior, which is a notable gap for a mutation operation.

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 input schema has 100% description coverage, with each parameter ('id', 'code', 'name') already described. The description adds no additional parameter semantics, so the baseline score of 3 is appropriate per the rubric.

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 'Update an existing retargeting pixel' clearly states the action (update) and the resource (retargeting pixel), and explicitly notes it operates on an existing entity, distinguishing it from create_pixel and get_pixel siblings. It precisely conveys what the tool does.

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 phrase 'Update an existing retargeting pixel' provides clear context that this tool is for modifying current pixels, implying it is not for creation or retrieval. However, it does not explicitly name alternatives or exclusions, such as mentioning create_pixel for new pixels, so it stops short of a perfect score.

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