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

Annotations already indicate read-only and idempotent behavior. The description adds context on the return structure (valid:true/false plus field-by-field error list) and the specific schema validated, which goes beyond the 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?

The description is two sentences, front-loaded with the core action, and every sentence adds value: validating against schema, listing fields, mentioning return type, and suggesting a complementary tool. No unnecessary words.

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 validation tool with one parameter and no output schema, the description covers input schema details, output format, and a useful pairing suggestion. It is fairly complete, though it could optionally mention potential edge cases or limits.

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?

With 100% schema coverage, the input schema only describes 'definition' as an object. The description significantly expands by enumerating the expected fields (definition_id, title, semver version, non-empty steps with subfields), adding crucial meaning for correct usage.

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 clearly states that the tool validates a checklist/SOP definition JSON against the CHECKRUN-1 schema, listing the required fields. It also distinguishes itself from the sibling tool checklist_step_receipt by noting the pairing for headless execution.

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 implies usage for validation before running a definition, mentioning pairing with checklist_step_receipt. However, it does not explicitly state when not to use it or compare with other similar siblings like checklist_verify_run.

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