lighthouse_audit

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

Annotations only provide readOnlyHint=false, which indicates potential side effects. The description adds the exclusion of performance but does not disclose other behavioral traits such as whether the audit navigates/reloads the page, the format of the report, or any prerequisites (e.g., an open page). The schema mentions navigation mode, but the description does not elaborate on side effects, making this acceptable but not rich.

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 long and directly front-loads the primary purpose. The first sentence states what the tool does, and the second provides a crucial exclusion and alternative. No unnecessary words or repetition, making it highly concise and 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?

The tool has moderate complexity (three optional parameters, no output schema). The description covers the main purpose and the key performance exclusion, which is helpful for tool selection. However, it lacks details about return values, prerequisites, and exact side effects (e.g., does it require an open page? does it save files?). Given the absence of an output schema, the description could be more complete, but it still provides adequate context for an AI agent.

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 100% for all three parameters, so the schema fully documents mode, device, and outputDirPath. The description does not add any parameter-specific meaning beyond the schema. It mentions the audit categories but does not map them to parameters, so the baseline score of 3 is appropriate.

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 'Get Lighthouse score and reports' for specific categories (accessibility, SEO, best practices, agentic browsing). It also explicitly excludes performance, which distinguishes it from the sibling performance_start_trace. The verb and resource are specific, and the scope is well-defined.

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 explicitly states what the tool does not cover ('This excludes performance') and directs the user to 'run performance_start_trace' for performance audits. This provides clear when-to-use and when-not-to-use guidance, including a named alternative. No other exclusions or alternatives are needed.

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