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

Annotations already declare the tool as read-only, idempotent, and non-destructive, so the description does not need to repeat that. It adds behavioral detail about supported YAML features (anchors, aliases, multi-document streams, scalar types), which goes beyond schema information. No contradictions 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?

Three sentences with no filler. The first sentence states the core action, the second gives relational context, and the third lists use cases and capabilities. Every sentence earns its place.

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?

The tool is simple with only two parameters and an output schema present, so the description does not need to explain return values. It covers purpose, usage scenarios, and supported YAML features, making it complete for an agent to decide and invoke correctly.

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%, so the baseline is 3. The description adds general input capabilities (nested objects, arrays, etc.) but does not provide additional parameter-specific meaning beyond what the schema already states for 'input' and 'multi'. There is no need for extra compensation.

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 uses a specific verb ('Parse') and resource ('YAML string') with a clear output ('equivalent JSON value'). It explicitly names the reverse sibling ('json_to_yaml'), distinguishing itself from related tools like json_to_yaml and xml_to_json.

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 clear use cases ('config files, CI/CD pipeline definitions, or OpenAPI specs authored in YAML') and indicates the tool's relationship to its reverse. While it does not explicitly state when NOT to use it, the reverse reference gives implicit exclusion, which is sufficient for a straightforward conversion tool.

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