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

With no annotations provided, the description carries full burden for behavioral context. It does not disclose whether the tool is read-only, idempotent, requires authentication, or handles edge cases like missing inputs (all parameters have defaults per schema). The output description is minimal (returns total and breakdown) without specifics on structure or potential errors.

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 sentences, front-loading the core purpose. It efficiently covers purpose, usage context, and a reference to related tools. Minor improvement could be removing 'Use for sustainability awareness' if it's redundant, but overall well-structured.

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 low complexity and presence of an output schema, the description adequately covers what the tool does and returns. It mentions the breakdown output, which complements the schema. However, it lacks details on potential limitations or error scenarios, but these are minor for a simple estimation tool.

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 input schema covers 100% of parameters with descriptions, so baseline is 3. The description groups parameters into categories (housing, transport, diet, lifestyle) but adds no new meaning beyond what the schema already provides. No parameter examples or value constraints are given.

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's purpose: estimating annual personal carbon footprint in tCO₂e. It specifies the inputs (housing, transport, diet, lifestyle) and output (total and breakdown), making it easy to understand what the tool does.

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 only mentions 'Use for sustainability awareness,' which is vague and provides no guidance on when to use this tool versus alternatives (e.g., calculate_carbon_sequestration). There are no exclusions, prerequisites, or explicit context for selection among the many sibling tools.

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