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

Annotations only cover the safety profile (readOnly, idempotent, non-destructive); the description goes beyond them with validation-only scope, the full return set, and the reader_capabilities available/unavailable semantics. The caveat that 'unavailable is not evidence of unsupported media' is a genuinely useful behavioral disclosure an agent could otherwise misread as a failure.

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-loads the core purpose and return values before the caveats, and nearly every sentence carries distinct information. The middle sentences are long and clause-heavy, which costs a little readability, but there is no filler.

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 correctly enumerates return fields and the available/unavailable states, and it warns that a different version may change options and output columns. The main shortfall is that required input parameters remain underspecified against 0% schema coverage.

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 0% for three required parameters, including a nested free-form decode_options object, so the description carries the documentation burden. It references family_id, family_version and decode_options conceptually and notes version-specific option/column differences, but never explains key formats or what decode_options accepts, leaving real gaps.

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?

Specific verb+resource: it resolves a certified Reader family/version and returns default-filled canonical decode options. It also draws a clean boundary against siblings by stating it only validates and 'does not acquire or decode bytes,' which distinguishes it from decode/register/run tools.

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 actionable direction: 'Use available metadata to diagnose MEDIA_TYPE and choose a compatible certified pin' and 'normalize it deliberately before registering a revision,' which ties it to register_recipe. It stops short of naming an explicit alternative tool or a negative case beyond the validate-only boundary.

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