convert_units

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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering safety. The description adds the behavioral note 'Works offline,' which is useful beyond annotations. However, it does not elaborate on return format or edge cases, though the output schema mitigates that. This aligns with the calibration example where a small extra context earned a 3.

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 and front-loaded. The core purpose and offline capability appear in the first sentence, followed by a clear Args list with examples. Every sentence serves a purpose, with no fluff or repetition.

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?

For a simple conversion tool with an output schema present, the description covers all necessary information to invoke it correctly: parameters, allowed unit values, and an example. It does not discuss invalid inputs or precision, but these are minor and not critical for a basic conversion. The offline note is a helpful addition. It is sufficiently complete.

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?

Schema coverage is 0% and the schema provides only titles with no descriptions. The description fully compensates by explaining each parameter: it gives an example for 'amount' and enumerates allowed values for 'from_unit' and 'to_unit' (btc, mbtc, bit, sat). This adds meaning the schema lacks, making it easy for an agent to supply correct values.

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 a specific verb and resource: 'Convert between Bitcoin units.' This distinguishes it from sibling tools focused on validation, derivation, or transaction queries, leaving no ambiguity about its function.

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?

Usage is implied rather than explicit. The description says it converts units, so an agent can infer when to use it, but there is no mention of alternatives or when not to use it. It does not provide any exclusion or comparison with sibling tools, so it lacks explicit routing guidance.

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