Get carbon intensity

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

With no annotations, the description must disclose behavioral traits itself. It adds the unit and the all-vs-single-region behavior, but does not explicitly state that it's read-only, describe the response format, or mention pagination, leaving some transparency gaps.

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 two sentences, front-loaded with the core purpose and unit, and contains no redundant 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?

The tool has 6 parameters, no annotations, and no output schema. The description covers the purpose, unit, primary usage modes, and relationship to a sibling tool. It does not describe the return shape, but the parameter schema covers usage details, making it sufficiently complete for an agent.

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 schema already provides descriptions for all 6 parameters, so the baseline is 3. The description enriches the semantics for 'iso' and 'latest' by explaining how omitting iso with latest=true retrieves all balancing authorities and passing iso returns one region.

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 explicitly states the tool returns grid carbon intensity in lbs CO₂/MWh, which is a specific resource and unit. It also distinguishes from the sibling get_fuel_mix by advising preference for emissions intensity questions.

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?

It provides explicit guidance on when to use this tool over alternatives ('Prefer this over raw fuel-mix when the question is about emissions intensity') and instructs how to query all regions versus one by toggling iso and latest.

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