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

Annotations already signal mutation (readOnlyHint=false) and non-destructive behavior (destructiveHint=false). The description adds the useful detail that the tool returns a layerId for subsequent operations. However, it omits behavior around duplicate IDs, overwriting, or idempotency, so transparency is only moderate.

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, front-loaded sentence that communicates the core action and the important return value without any wasted words. It is concise and appropriately sized.

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 marker-adding tool with fully documented parameters, the description covers the essential return value (layerId), which is particularly important given there is no output schema. It could add more context about duplicate IDs or overlay behavior, but it is mostly complete.

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 coverage is 100%, so all six parameters are already documented with descriptions. The tool description adds little beyond mentioning longitude/latitude and the return of layerId; it does not provide extra semantics for id, size, color, or label beyond what the schema already states.

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 states that the tool adds a marker point at a specified longitude/latitude and returns a layerId for later operations. It is specific and action-oriented, though it does not explicitly distinguish it from sibling add* tools like addLabel or addBillboard.

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 this tool is for adding marker points, but it does not provide explicit guidance on when to use it versus alternatives such as addBillboard or addLabel. No when-to-use or when-not-to-use context is given beyond the core action.

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