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

No annotations are provided, so the description carries full responsibility. It discloses rate limits ('20 anonymous calls/caller/24h; then 100 free calls/key/30d') and notes that sustained use requires an active Builder. It also clarifies the nature of results (federal status + state/utility programs for US, qualitative officially-sourced guidance for other countries). It does not detail the exact response format, but the key behavioral constraints are covered.

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 only two sentences plus a compact rate-limit note. Every clause serves a purpose: scope, regional behavior, explicit use case, and operational limits. There is no redundant or filler text.

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?

Given two optional parameters and no output schema, the description covers the main usage scenarios, explains what type of results to expect for each branch, and includes rate limits and builder requirements. It gives an agent enough context to select the tool correctly and set user expectations.

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%, so the baseline is 3. The description adds value by explaining the interplay between parameters: US ZIP returns federal/state/utility programs, while other countries require country code and return qualitative guidance. This conditional logic is not present in the schema and helps the agent decide which parameters to populate.

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 'Clean-energy incentive guidance for any address WORLDWIDE' and breaks down the function by geography (US ZIP vs other countries). It explicitly lists the types of questions it answers (rebates, tax credits, utility programs for solar, batteries, heat pumps, efficiency work), distinguishing it from siblings like estimate_production or find_local_installers.

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 explicit trigger: 'Use whenever a user asks what rebates, tax credits, or utility programs apply...' It also gives conditional guidance for US versus non-US inputs, clarifying when to pass country and when to use just zipCode. No alternatives are named, but the use case is precise and unambiguous.

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