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

Beyond the annotations (readOnlyHint=true, destructiveHint=false, idempotentHint=true), the description discloses meaningful behavioral boundaries: it verifies checksum and structure without querying the blockchain or checking balances. This gives an agent a precise model of what the tool can and cannot do, with no contradiction.

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 three dense sentences with the core purpose front-loaded. Every sentence adds distinct value: what the tool does, what inputs it supports, and what it explicitly avoids. The source URL is supplemental but not bloated.

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 tool's moderate complexity, a single-parameter schema, and rich annotations plus an output schema, the description covers all necessary invocation details: purpose, accepted formats, networks, and limitations. An agent has enough context to select and call the tool correctly.

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 schema already describes the single 'address' parameter at 100% coverage, establishing baseline 3. The description goes further by enumerating valid address variants (legacy Base58Check, Bech32/Bech32m, SegWit, Taproot, mainnet/testnet), which materially helps an agent construct a valid parameter value.

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 uses a specific verb ('Check whether') and resource ('a Bitcoin address is valid') and clearly distinguishes this tool from sibling validators like hopi_iban_validator and hopi_eth_address_checksum. It further narrows scope by naming supported address formats, networks, and what it does not do.

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 makes the tool's context clear: it is for Bitcoin address validation only, covering specific formats and networks. It also includes a when-not-to-use signal ('Does not query the blockchain or check balances'), though it does not explicitly name an alternative tool for balance lookups.

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