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

Annotations already establish the safe, read-only, idempotent profile, so the bar is lower; the description still adds real operational context: 1 credit per call, a 1 MiB output cap, inline file delivery, and the meta {from, to} payload. It does not, however, explain error behavior beyond 'line-accurate error messages'.

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?

Front-loaded with the core action and features, then terse cost/output facts. The output clause is telegraphic ('converted.json or converted.yaml; meta: {from, to}') but earns its place; no filler sentences.

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?

With no output schema, the description appropriately specifies the return shape (inline file, media type, filename, meta) and the size limit, which is what an agent needs. Minor gap: it does not reconcile the 2 MB input cap with the 1 MiB output cap.

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 coverage is 100%, so every parameter (from, to, input, indent, minify, sort_keys) is already documented in the schema with defaults and enum meanings. The description only gestures at these options without adding format or interaction details beyond what the schema states.

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?

Names a specific verb (Convert) plus both resources (JSON and YAML text), and the feature list (safe parsing, indent, key sorting, minify) pins down the exact scope. It is clearly distinguishable from siblings like image_convert or tabular_convert.

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?

Gives practical framing in the form of cost (1 credit per call) and size bounds, but never states when to pick this tool over alternatives such as tabular_convert or json_schema_validate. Usage is only implied by the tool's obvious purpose.

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