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

No annotations provided, so the description must carry the burden. It states the output categories but does not disclose whether it parses .env format (key=value) or treats lines as strings, nor does it describe the output structure or handling of comments/blanks.

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 concise at two sentences, but the second sentence 'When: ...' is redundant and could be integrated into the first. No uninformative details.

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 no output schema, the description lists the types of differences (only_in_a, only_in_b, changed) but lacks specifics on the return format (e.g., array of objects, key-value mapping) and does not cover edge cases like keys missing in both files or malformed lines.

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%. The description implies that parameters 'a' and 'b' are .env file contents, but does not clarify whether they are file paths or raw strings. No additional parameter details are provided beyond the parameter names.

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?

Clearly states the verb 'Diff' and the specific resource '.env files'. Lists the output categories (only_in_a, only_in_b, changed values), which differentiates it from general text diff tools like text_diff.

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?

No explicit guidance on when to use this tool versus alternatives (e.g., text_diff or env_parse). The 'When:' phrase merely restates the purpose rather than providing contextual usage advice.

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