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

With no annotations provided, the description carries the full burden and excels: it discloses live EU ETS price usage, phase-in rate ramp, punitive mark-up for unverified emissions, Article 9 deduction mechanism, and multi-year projection behavior. These are meaningful behavioral traits not inferable from the schema.

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 dense paragraph, but it is front-loaded with the core purpose and then systematically covers scenarios and parameter effects. Every sentence adds value, though slightly more formatting or bullet structure would improve scannability.

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 9 parameters, no output schema, and no annotations, this description is remarkably complete: it explains the two output scenarios, the phase-in timeline, the price source, deduction logic, parameter-triggered behaviors, and projection capability. It does not elaborate on errors or edge cases, but covers all essential operational aspects.

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?

Although the schema already describes all 9 parameters (100% coverage), the description adds crucial behavioral context: actual_emissions triggers an optimization block, carbon_price_paid applies Article 9, project enables forecasting, and ets_price overrides the live price. This goes well beyond the schema's property descriptions.

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 opens with a clear action verb and resource: 'Calculate CBAM embedded emissions and estimated EUR liability for an imported good.' It further specifies sectors, phase-in rates, and scenario distinction, which distinguishes it from siblings like batch calculations or emissions-only 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 provides clear guidance on when to pass optional parameters ('Pass actual_emissions...', 'pass carbon_price_paid...', 'pass project=true') and explains the effect of each. However, it does not explicitly name alternatives or exclusions, leaving the choice versus siblings like calculate_cbam_batch implicit rather than stated.

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