bind_variable

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

Despite no annotations, the description discloses the special behavior for 'fills'/'strokes' (binding the first solid paint's color) and the use of different underlying methods, plus the type matching requirement. It does not cover error handling or side effects, but it provides meaningful behavioral context.

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, information-dense paragraph that front-loads the purpose, then details special cases and constraints. No wasted words; each sentence contributes.

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 3-parameter tool with no output schema, the description covers the primary usage, supported properties, and a key constraint. It lacks explicit return-value or error information, but the operation is straightforward enough that the description is nearly 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?

The schema already describes all three parameters (100% coverage), so the baseline is 3. The description adds value by explaining which property values use which binding method and by listing the full set of supported properties, which clarifies the 'property' parameter's semantics.

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 'Bind a variable to a node property' and enumerates the specific property categories and the two distinct methods involved. This differentiates it from sibling tools that set static values or create variables.

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 explicit guidance on when to use vs alternatives; the description focuses on mechanics rather than decision criteria. The constraints like 'Variable type must match the property' are prerequisites but not usage recommendations.

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