Knitting and crochet reference

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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so the safety/idempotency profile is covered structurally. The description adds useful context about the nature of the data (which reference categories exist and how they are cross-regional), but discloses no runtime behavior beyond that.

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, front-loaded with the resource scope before the usage hint. The first sentence is a dense list but every clause carries new information; minimal waste.

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?

An output schema exists so return values need no explanation, and annotations cover safety. The description sufficiently covers what data is available and how to query it; the only gap is sibling disambiguation against the conversion/gauge tools.

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 67%, and the description adds real value by enumerating the topics the `topic` enum encodes and giving concrete `lookup` examples ("4mm", "US 8", "H", "DK", "8 ply", "ssk", "htr") that clarify accepted value formats beyond the schema's terse description.

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?

States a specific resource (reference tables) with concrete scope: needle/hook sizes, yarn weights across regions, US↔UK term mappings, and abbreviations. This is clearly distinct from the sibling tools, which are pattern/yarn search and calculation/conversion utilities.

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 tells the agent how to use `lookup` (to find one entry) with concrete input examples, which is helpful. However, it gives no guidance on when to prefer this static reference over related siblings like adjust_for_gauge or convert_yarn_amount, nor any exclusions.

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