SiteAudit MCP

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

Annotations provide readOnlyHint=true, and the description adds valuable behavioral context beyond that: it discloses execution time ('Takes 15-30 seconds to complete'), mentions it uses 'Google's real Lighthouse engine', and specifies the scope of returned data (scores, Core Web Vitals, top 5 opportunities). This enhances understanding of the tool's operational characteristics.

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 efficiently structured with four focused sentences: first states the core function, second details return values, third adds implementation context, fourth provides timing information. Every sentence adds value with zero wasted words, and key information is front-loaded.

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 annotations (readOnlyHint), 100% schema coverage, and an output schema exists, the description provides excellent contextual completeness. It covers purpose, return values, implementation details, and execution timing - everything needed to understand the tool's role and behavior without duplicating structured data.

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?

With 100% schema description coverage, the schema already fully documents both parameters. The description doesn't add any parameter-specific information beyond what's in the schema (URL to audit, mobile/desktop strategy). The baseline score of 3 is appropriate when the schema carries the full parameter documentation burden.

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 specific action ('Run Google Lighthouse via PageSpeed Insights API') and resources involved ('performance, accessibility, SEO, and best-practices scores plus Core Web Vitals'). It distinguishes from siblings like 'performance_audit' or 'seo_audit' by specifying it's a comprehensive Lighthouse audit that returns multiple categories of scores, not just one aspect.

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 through mentioning what the tool returns and execution time, but doesn't explicitly state when to use this vs. alternatives like 'performance_audit' or 'full_audit'. It mentions 'top 5 performance optimization opportunities' which suggests optimization focus, but no clear guidance on tool selection among siblings.

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