render_get_codecs

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

The description accurately reflects a read-only operation, consistent with the readOnlyHint annotation. It does not add deeper behavioral details (e.g., error handling if format is invalid, or whether results depend on project settings), but annotations already cover the safety profile, so this is acceptable.

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, clear sentence with no redundant wording. It immediately states the action and the object, making it concise and well-structured.

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, single-parameter read-only tool with a rich schema and output schema, the description is sufficiently complete. It covers the core behavior, while the schema supplies parameter details and the output schema handles return structure. The only minor gap is the lack of explicit mention of potential error conditions, but this is not critical given the low complexity.

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% for the single parameter, providing example values and a pointer to render_get_formats(). The tool description itself adds no additional parameter semantics, so the baseline of 3 applies.

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 it returns available codecs for a given render format, specifying both the action and the resource. This distinguishes it from sibling tools like render_get_formats (which returns formats) and render_get_format_and_codec (which returns the current format/codec pair).

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 usage is implied: you need to know codecs for a specific format. The parameter description suggests using render_get_formats() to obtain valid format names, providing a weak cross-reference. However, there is no explicit guidance on when to prefer this tool over related siblings such as render_get_format_and_codec, nor any exclusion criteria.

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