compare-grammars

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

No annotations are provided, so the description must carry the full burden. It clearly discloses the output behavior by listing the returned categories (common, unique, modified rules, statistical summary) and implies a read-only operation through the verb 'compare.' It does not mention potential error conditions or side effects, but for a comparison tool this is acceptable.

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 well structured with a clear first sentence, a 'When to use' section, an example, and a bulleted output list. It is slightly longer than necessary, but every section adds value and the information is easy to scan.

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?

The tool has four parameters with a logical mutual exclusivity (file path vs. content), but the description does not explicitly state that users must provide either from_file1/from_file2 or grammar1_content/grammar2_content. The output schema is absent, so the description's output list helps, but the missing requirement explanation leaves a notable gap.

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 schema covers all four parameters descriptively (e.g., 'overrides grammar1_content'), so the baseline is 3. The description adds an example usage with actual file paths, which helps clarify parameter format, but it does not introduce new semantic details beyond the schema.

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 the tool's function: 'Compare two ANTLR4 grammars side-by-side to identify differences.' It uses a specific verb ('compare') and resource ('two ANTLR4 grammars'), which distinguishes it from sibling tools like compare-profiles, which compares profiles rather than grammars.

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 provides explicit use cases: 'Understand changes between versions, merge grammars, or analyze variations.' It also includes an example invocation. However, it does not explicitly mention alternatives or state when not to use this tool, so it falls short of a 5.

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