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

Annotations already declare readOnly, idempotent, non-destructive, openWorld, so the safety profile is covered. The description adds real operational context beyond that: the tsconfig.json prerequisite and the meaning of lookupOrigin/fallbackReason, which tells the agent how slug confirmation may vary.

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?

Front-loaded purpose sentence, then compact Args/Returns/Examples blocks. Every element earns its place; nothing is redundant with the schema.

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?

With an output schema present, return values need not be explained, yet the description still names the key fields. A single-param, read-only lookup tool is fully specified: purpose, prerequisite, input meaning, and example all covered.

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% and there is only one parameter, so baseline is 3. The description goes further by clarifying slug is a style identifier and demonstrating how a natural-language request maps to a slug value, which the bare schema does not convey.

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 verb and resource: 'Get the one-line shadcn CLI command that installs a style's color theme (light + dark) into a shadcn project.' This separates it cleanly from siblings like get_style_tokens or get_component_recipe without needing the schema.

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?

Provides a concrete trigger example ('how do I install the synthwave theme?' -> slug: synthwave') and a hard prerequisite (tsconfig.json required or the shadcn CLI errors). It does not name a competing sibling or say when NOT to use it, so it falls short of a 5.

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