btc_balance

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

No annotations are provided, so the description carries the burden. It discloses the external source (blockchain.info) and scope (quick balance check), but omits details about error behavior, rate limits, or response format. This is adequate but not comprehensive.

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 two sentences, front-loaded with the core purpose, and every sentence adds value. No redundant or vague wording.

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 single-parameter, read-only tool, the description adequately covers purpose, source, and scope. The lack of an output schema is partially mitigated by stating the balance is in satoshi, but the exact return structure is not specified. Overall, it is complete enough for simple 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?

Schema coverage is 100%, with the address parameter described as 'Bitcoin address.' The description adds context about the result unit (satoshi) and source, but does not add meaning beyond the schema for the parameter itself. 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?

Description specifies a clear verb ('Get') and resource ('Bitcoin address balance in satoshi from blockchain.info'), and distinguishes itself from siblings like btc_tx by noting 'without full transaction history.' This makes the tool's purpose unambiguous.

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 phrase 'Quick balance check without full transaction history' provides clear context for when to use this tool (simple balance lookups) versus tools that provide transaction history. However, it does not explicitly name alternative sibling tools, so it falls short of a 5.

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