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

Annotations provide readOnlyHint=true, and the description adds meaningful behavioral context: it's deterministic (not an LLM call), always instant, and never consumes archive or LLM credit. It also discloses the return behavior (returns which tool to call, what next, and what NOT to start with). This adds value well beyond the annotation.

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 dense paragraph, front-loaded with the core purpose and value proposition (deterministic, instant, no credit consumed). It packs substantial guidance efficiently, though it is slightly long near the end with the example goal enumeration and tool-name list.

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 single-parameter, deterministic routing tool with readOnlyHint annotation and an output schema, the description fully covers what the agent needs: what it does, when to invoke it (before guessing between similarly-named tools), the expected input format, and the nature of the output. No gaps identified.

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% for the single 'goal' parameter, which is described as 'Plain-English description of what you're trying to do.' The tool description elaborates with concrete examples of valid goal phrasings, adding value beyond the bare schema. Baseline 3 is appropriate given high schema coverage.

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 this is a deterministic routing lookup that returns which tool to call first/next and which similar tools NOT to use. The verb+resource is specific ('give it a goal, returns exact routing'), and it explicitly distinguishes itself from sibling tools by naming them (palette_specify vs interior_specify vs house_specify).

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 gives explicit when-to-use guidance ('Use this before guessing between similarly-named tools') and provides concrete example goals ('I have a brand colour and want to check it against competitors'). It names the classifications of tools it disambiguates between, giving clear alternatives-defining context.

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