derive_entropy_bip85

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

Annotations indicate read-only and non-destructive, which the description reinforces by describing a deterministic derivation that works offline. It additionally discloses an environment requirement (MCP_BITCOIN_ALLOW_MNEMONIC=true) and clarifies that it operates on a master seed, which the schema alone does not convey. The description does not contradict annotations.

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 compact multi-line block that front-loads the key action and purpose. It then lists parameters efficiently. Some redundancy exists (e.g., 'works offline' could be inferred, but it does add safety context).

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 complexity (5 parameters, 0% schema coverage) and the presence of an output schema, the description fully covers what the tool does, key constraints (works offline, env requirement), and parameter semantics. It does not state the return format, but with an output schema present, that is not required. It also distinguishes from siblings.

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% (no property descriptions), so the description must carry all meaning. It explains the role of each parameter: mnemonic as the master seed, index for derivation, passphrase as optional, child_mnemonic_words for selecting seed phrase length or raw entropy, and num_bytes for entropy length. This adds significant value beyond the bare schema.

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?

States a specific verb ('Derive'), resource ('child seed or entropy from a master seed'), and the exact standard (BIP-85). Clearly distinguishes from sibling tools like 'generate_mnemonic' (which creates new seeds) and 'derive_from_path' (which derives at a generic BIP-32 path).

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?

Explains when to use this tool for BIP-85 derivation and distinguishes between child seed phrase and raw entropy via the parameters. However, it does not explicitly state when NOT to use it or mention alternatives; the sibling list is large, but the description implies usage for BIP-85, which is distinct.

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