99 multi-estimate (pMultiEstimatePrice)

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the bar for added value is met by the description's extra context: the HTTP transport (POST), the response envelope ('JSON 200 errno' — critical for error detection since errors arrive as 200s with errno codes rather than HTTP failures), the lack of authentication, and the side-effect confirmation that no car is requested. All complement rather than contradict the annotations.

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 13 words with zero filler; the safety-critical facts (read-only, endpoint, response envelope, no token) are front-loaded. It is slightly under-sized for a tool with 6 parameters and two non-obvious enums, but as pure conciseness it is exemplary.

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 6 parameters at 0% schema coverage, two opaque enums, and no output schema, the description carries a heavy burden and covers only the safety/error-handling layer. Missing are the core use case, parameter semantics, response structure beyond errno, and differentiation from the near-namesake ninenine_estimate sibling — genuine gaps that would force an agent to guess.

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 0%, so the description inherits the full burden of explaining parameters — and it mentions none of them. An agent cannot learn from either source what the from/to lat-lng pairs represent (origin/destination), what privacy_mode does with its opaque 'summary/structured/raw' enum, or how response_format affects output beyond its self-evident name.

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 names a specific verb+resource ('Read-only POST pMultiEstimatePrice') and adds a disambiguating note ('Does not request a car') that separates it from request_ride. However, the business purpose — multi-route price estimation — is only implied via the title and endpoint name; it is never explicitly stated that this computes fare estimates.

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 provides useful context: it is safe (read-only), requires no token, and does not request a car, which partially excludes the request_ride path. But it offers no explicit when-to-use guidance and never mentions the most likely alternative sibling, ninenine_estimate, so an agent gets no help choosing between single and multi estimate.

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