Lint PHP File

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

The description discloses that it runs php -l, catches only parse-time errors, and does no static analysis, adding valuable behavioral context beyond the annotations (readOnlyHint, idempotentHint, destructiveHint). No contradictions.

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?

Two concise sentences that front-load the action and key details without any unnecessary words or redundancy.

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 simple tool with one parameter, no output schema, and clear annotations, the description provides complete context: what it does, how it works, and its limitations. No gaps remain.

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 already fully describes the single parameter 'filepath' with a clear description and example. The tool description does not add additional parameter semantics beyond what is in the schema, meeting the baseline for high coverage.

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 explicitly states it checks a PHP file for syntax errors using php -l, and distinguishes itself by specifying it only catches parse-time errors and does not perform static analysis, clearly differentiating it from sibling tools like run_psalm or run_phpcs.

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 context by specifying the tool's scope (syntax-only, no static analysis), but it does not explicitly state when to use or when to prefer alternatives. Still, the clarity about limitations provides useful guidance.

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