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

Annotations already declare readOnlyHint=true, so the description adds value by explaining the score's components, history to 1976, and monthly updates. This context goes beyond the annotations and helps the agent understand data freshness and scope.

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 compact and front-loaded with the core return value, followed by use cases and update frequency. It is slightly dense due to the parenthetical components and field list, but every clause contributes useful information.

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 no output schema, the description lists all key return fields and indicates the 0-100 scale. It also covers historical depth, update cadence, and typical use cases, making it sufficiently complete for a read-only data lookup tool.

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 parameter schema fully documents the optional 'days' parameter, including the Gold tier requirement and fallback behavior. The main description adds no parameter details, but with 100% schema coverage, a baseline score of 3 is appropriate.

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 returns a 0-100 US semiconductor fab-utilization tightness score and lists the specific output fields. This is a specific verb+resource that distinguishes it from the many sibling tools by its unique domain and composition.

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 explicitly says 'Call when the user asks about chip supply tightness, fab capacity, or export-control exposure to chip lead times' and extends to procurement and lead-time scenarios. It gives clear context but does not mention alternatives or when not to use the tool.

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