Compare a site with its rivals on the same measurements

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

With no annotations, the description carries the full burden. It usefully constrains scope ('public sites', 'free public signals only') and hints at the shared measurement basis, which is helpful context, but discloses nothing about authorization needs, rate limits, latency, or failure modes for non-public URLs.

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?

Three short sentences, front-loaded with the core action before the usage scenario. The middle sentence is slightly conversational but each clause still carries routing value, so little is wasted.

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?

There is no output schema and no annotations, so the description is the only source of behavior. It says results come back 'side by side' but never enumerates the six measurement areas an agent would need to interpret the output, leaving the return shape underspecified for a comparison tool.

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 67%, with urls and pages already documented in-schema (including the 'first one is yours' ordering convention). The description reinforces the two-to-four site bound, matching the schema's min/max, but says nothing about the undocumented lang enum or what 'six areas' comprises. Adequate but not compensating for the gap.

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?

States a concrete verb and resource: it runs 'the same six-area measurement on two to four public sites' and returns results 'side by side'. This makes the multi-site comparative nature clear and implicitly separates it from the single-site audit_site sibling, though it never names that sibling explicitly.

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?

Gives concrete triggering scenarios ('why a competitor is being quoted instead of them', 'where the gap actually is'), which tells the agent when this tool applies. It stops short of naming alternatives like audit_site or run_gates, so the routing decision for a single-site case is left to inference.

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