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

Annotations provide no behavioral hints (all false), so the description carries the burden. It discloses that the tool returns an entityId, which is a useful behavioral detail not in the schema or annotations. However, it does not mention other behaviors such as whether the polyline is immediately visible, whether it replaces existing entities, or any prerequisites like a loaded map.

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 a single concise sentence that front-loads the action and resource, and includes the return value. No wasted words.

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?

The tool has 5 parameters and no output schema, and there are many sibling add* tools. The description gives only the purpose and return, but lacks usage guidance, behavioral details, and any context about coordinate format or return type beyond the schema. This makes it incomplete for an agent making an informed invocation decision.

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 100%, so all five parameters are already documented with descriptions. The description adds no additional parameter meaning beyond the schema, so the baseline score of 3 is appropriate.

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?

Description uses a specific verb "添加" (add) with resource "折线" (polyline) and clarifies with "路径、线段" (path, line segment). It also states the return value (entityId), which distinguishes it from sibling add* tools like addPolygon or addLabel. Scope "在地图上" is clear.

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 implies usage for adding polylines but does not provide explicit guidance on when to choose this over sibling tools such as addPolygon or addLabel. No alternatives or exclusions are mentioned, leaving the agent to infer from the tool name alone.

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