Point: Tangent from external point

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

The description adds value beyond readOnlyHint annotation by specifying the return format ({x, y}) and the error condition (raises if from-point inside circle). No contradictions with 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?

Two sentences with no wasted words. The main action is stated first, then extra details. Perfectly concise for the tool's simplicity.

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?

Given the presence of an output schema, the description covers the essential behavior (tangent computation, error condition). It is sufficient for the tool's geometric nature, though it omits any mention of the reference parameters (ref_x, ref_y) behavior.

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 the description is not required to explain parameters. However, it adds no additional meaning beyond the schema, which is adequate for a baseline of 3.

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 the tool computes a tangent point on a circle from an external point, with a specific verb ('Compute') and resource. It is distinct from sibling tools like 'point_intersection' and 'point_from_snap'.

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 when a tangent point is needed, but lacks explicit guidance on when to use this tool versus alternatives (e.g., point_intersection). No exclusion criteria or prerequisites mentioned.

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