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

With no annotations provided, the description carries the full burden of behavioral disclosure, but it only says 'Calculate CO2e emissions for a flight.' It does not mention methodology, data sources, assumptions, output format, or any safety/read-only traits. This is essentially a restatement of the tool name.

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 a single sentence with no wasted words, which is good for conciseness. However, it offers no additional useful structure or detail beyond the bare purpose, so it does not reach a full 5.

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 is relatively simple with well-documented parameters, but there is no output schema and no annotations. The description does not explain return values, methodology, or edge cases, leaving some gaps for effective use.

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 description coverage is 100%, so each parameter already has a description. The tool description adds no additional meaning beyond what the schema provides. Baseline 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 calculates CO2e emissions for a flight, using a specific verb and resource. It distinguishes from sibling tools like calculate_emissions_freight and calculate_emissions_activity by specifying 'flight'.

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 flight emissions but does not explicitly state when to use this tool over alternatives. No mention of alternatives or exclusions is present; the guidance is only implicit in the name and description.

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