list_emissions

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

No annotations are provided, so the description carries the full burden of disclosing behavior. It mentions filtering but does not disclose pagination behavior beyond the schema's nextToken parameter, nor does it explain whether the output includes aggregated or per-vessel details, whether results are sorted, or if any data is excluded. For a list operation with pagination, this is a notable gap in behavioral transparency.

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, concise sentence that is front-loaded with the main action ('List global vessel emissions data') and immediately identifies the key parameter ('optional year filter'). Every word earns its place; there is zero redundancy or filler.

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 that there is no output schema and no annotations, the description provides only a basic overview. It successfully communicates the core purpose and the main filter, but it omits details about pagination semantics (other than the schema's nextToken) and what constitutes 'emissions data' (e.g., CO2, NOx). For a list tool with no output schema, the description could be more complete to guide agents on expected results.

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 covers 100% of parameters with descriptions (limit, period, nextToken). The description adds the insight that 'period' is a reporting year filter, which aligns with the schema, and it mentions the year filter as the key optional feature. However, it does not add detail beyond the schema's own parameter descriptions, so the baseline 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 'List global vessel emissions data with optional year filter' clearly states the verb (list), resource (global vessel emissions data), and key capability (optional year filter). It distinguishes itself from sibling tools like get_vessel_emissions (which likely targets a specific vessel) by explicitly saying 'global', though it does not directly name an alternative. Thus it's clear but slightly short of fully differentiating from related emission tools.

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 listing emissions data, and the 'optional year filter' hints at when to apply filtering. However, it does not provide explicit guidance on when to use this tool versus alternatives like get_vessel_emissions for a specific vessel or search_vessels. There are no exclusions or alternative tool names, so it's adequate but lacks explicit decision support.

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