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

Annotations indicate readOnlyHint and openWorldHint. Description adds critical behavioral context: pay-per-call ($3.00 via x402 on Base or Solana), concurrent scanning, and payment_required response handling. 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?

Concise and well-structured: function first, then usage context, then payment details. Every sentence adds value, no fluff.

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 complexity (competitive analysis with payment), the description covers output (scores, winners, gaps, fix code, projected scores) and the payment flow. No output schema needed as description covers return value sufficiently.

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 coverage is 100% with descriptions for url, pages, competitorUrl. The tool description adds no significant meaning beyond the schema; it merely restates that url and competitorUrl are site URLs. Baseline 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 'Competitive gap analysis — scans two sites concurrently, shows side-by-side scores...' which is a specific verb+resource. It distinguishes from sibling tools like scan_site (single site scan) and audit_site (single site audit).

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?

Explicitly states when to use: 'Use this when the user wants to benchmark against a competitor or when scan_site detects competitors in the AI Identity Card.' Also provides payment handling guidance.

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