Atmospheric CO2 (Keeling Curve)

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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint. The description adds valuable context: data source (NOAA ESRL), temporal coverage (since 1958), and default range (last 10 years), enhancing transparency beyond structured fields.

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 concise with three front-loaded sentences: first identifying the tool, second detailing the data, third setting defaults and source. Every sentence adds value without redundancy.

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 the tool's simplicity (single optional parameter, output schema present, full annotations), the description provides sufficient context. It covers what, source, frequency, and default behavior, making it complete for an agent to select and use correctly.

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 describes the 'years' parameter completely (type, range, default, meaning). The description does not add further parameter information beyond the schema, so baseline score 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 explicitly states the tool provides 'Atmospheric CO2 concentration' from the Keeling Curve, specifying units (ppm), frequency (monthly), and time span (since 1958). It clearly distinguishes from sibling tools like arctic_ice or methane by naming the specific indicator.

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 implies usage for CO2 data and mentions default behavior (10 years) but does not explicitly state when to use it over alternatives or provide exclusions. Sibling tools are differentiated by indicator type, but no direct usage guidance is given.

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