list_sources

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

With no annotations provided, the description carries the behavioral disclosure burden. It honestly conveys that the tool returns a list of available sources and previews the returned attributes (form, key requirement, notes). The verb '列出' implies a read-only operation, which is sufficient for a simple zero-parameter list tool, though it does not explicitly state side-effect safety.

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 one compact line, front-loading the core action and resource, then adding the most useful output detail in parentheses. There is no filler or redundancy; every element contributes to explaining what the tool does.

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?

This is a simple zero-parameter list tool with no output schema, so the description carries the full burden of explaining what the agent will receive. It covers the output contents reasonably well and is complete enough for a basic invocation. It could be slightly richer by noting how this list relates to discover_hotspots, but the missing guidance is not critical for execution.

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 the schema is empty with full coverage, so there is nothing for the description to clarify. For a no-parameter tool, the baseline of 4 applies because no parameter explanations are needed; invoking the tool is trivially unambiguous.

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 gives a specific verb '列出' (list) and clearly identifies the resource: available hotspot sources. The parenthetical '形态、是否需密钥、实测备注' conveys the kind of information returned, making the tool's purpose clear. However, it does not explicitly contrast itself with the sibling tool discover_hotspots, so it stops short of full differentiation.

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?

No guidance is given about when to use this tool versus discover_hotspots, nor any criteria for when listing sources is appropriate. The intended use is only implicit in the word '列出' (list). The agent would have to infer the boundary between listing sources and discovering hotspots without explicit direction.

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