99 capabilities

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description's burden is lower. It adds useful context about the unofficial scope and gated writes, but it does not define what 'gated' means in practice or describe the response format. No contradiction with 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 extremely concise: one sentence states the tool's purpose and a second clause clarifies scope. Every word earns its place, with no repetition of the title or schema details.

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?

For a simple read-only tool with one optional parameter and no output schema, the description gives enough high-level understanding of what the tool returns. However, it omits any mention of the response_format parameter and provides no explicit guidance on when the tool should be used, leaving a moderate gap in completeness.

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%, and the description does not mention the only parameter, response_format, at all. The enum and default in the schema are self-documenting, but under the low-coverage rule the description was expected to compensate and did not.

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 indicates the tool reports what this unofficial MCP can read and which writes remain gated, so the resource and scope are identifiable. It lacks a direct verb such as 'lists' or 'returns' and does not distinguish it from sibling ninenine tools, though it does distinguish it from 99Food and 99Pay.

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?

There is no guidance on when to call this tool relative to its siblings like ninenine_connection_status or ninenine_request_ride. The 'Not 99Food or 99Pay' note is an external disambiguation, not usage direction. The phrase 'which writes stay gated' implies it could be used before write operations, but that is not made explicit.

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