Validate JSON

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

Annotations already indicate readOnlyHint=true, destructiveHint=false, idempotentHint=true, so the tool is safe and non-destructive. The description adds that it shows line/column on errors, which is useful. However, it does not mention file size limits, encoding assumptions, or whether it performs strict JSON validation. With annotations covering safety, a score of 3 is appropriate.

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 short and to the point, with a clear args/returns structure. It could be slightly more concise by removing the 'Args:' label, but overall it is 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?

Given the tool has only one parameter and annotations cover safety, the description is adequate. However, it lacks details about the return format (just says 'validation status', not whether it's a boolean or object). Also, no mention of error handling for missing files or invalid inputs. For a simple tool, this is acceptable but not comprehensive.

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?

The parameter 'path' already has a description in the schema (100% coverage). The description adds no extra meaning beyond what the schema provides. Therefore baseline 3 is correct.

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 it validates a JSON file and shows detailed error information. It distinguishes from sibling tools like fc_fix_json (which likely fixes errors) and fc_read_file (which reads without validation). However, it could be more specific about the validation performed (e.g., schema validation vs. syntactic validity).

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 when you need to validate a JSON file and get error details. It does not explicitly say when not to use it or mention alternatives like fc_fix_json for fixing errors. Given the sibling list, there are related tools but no guidance on choosing between them.

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