Percent-grid positions

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

No annotations are provided, so the description bears the full burden of behavioral disclosure. It does disclose two genuine behavioral traits: the webhook_url is stripped from responses, and one grid's trades/chart are HTTP-only. However, it omits other traits an agent might need, such as response shape, ordering, or any pagination/limits — though for a zero-input listing tool this is a moderate, not severe, gap.

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 with no filler; the core purpose is front-loaded first, followed by use-cases and the sibling routing note. Each sentence earns its place, though the mixed-language use-cases (Chinese) add minor friction for English-reading agents.

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 no-input listing tool with no output schema, the description covers the essentials: what is returned (positions with performance), the data source, a data-hygiene caveat (webhook_url stripped), and the routing rule for deeper grid detail. It's reasonably complete given the tool's low complexity, though it stops short of describing the return format.

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?

The tool has zero parameters and schema coverage is trivially 100%, so the baseline of 4 applies. The description reinforces this by explicitly stating 'No inputs', which removes any doubt about invocation requirements. Nothing more is needed semantically since there are no parameters to document.

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 the resource precisely ('All %-grid positions with performance') and names the data source (GET /api/external/ro/grid), which clearly distinguishes it as the grid-position listing among siblings like ro_holdings and ro_logs. It lacks an explicit verb like 'List' or 'Fetch', but the phrasing strongly implies a read/listing operation, so intent is unambiguous.

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 trigger use-cases ('Use for 网格赚了没 / 哪些网格开着'), telling the agent exactly when this tool applies. It also states an explicit exclusion with a sibling pointer ('One grid's trades/chart are HTTP-only (see ro_catalog)'), which routes the agent away when it needs trade-level detail. Strong guidance, though it could be slightly more explicit about when NOT to use it in favor of ro_holdings/ro_logs.

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