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

Annotations already declare readOnlyHint=false, idempotentHint=true, and openWorldHint=true, but the description adds real value beyond them: the exact cost (0.005 USDC on Base mainnet) and the instruction to preserve the idempotencyKey across retries. That explains the payment-driven non-read-only profile. It still omits what a successful call returns.

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?

Three tight sentences with no waste, and the operational essentials (cost, idempotency) are front-loaded after the resource. The opening 'Read getblock' phrasing is slightly redundant with the name but costs little.

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 paid, non-read-only tool with positional array parameters, the description never explains the argument structure or the returned block payload, and there is no output schema to fall back on. The cost/retry context is good but the call itself remains under-specified.

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 50% and the two positional array items (a 64-hex block hash and a 0/1 verbosity flag) carry no descriptions in either the schema or the description. An agent must guess that item 1 is a block hash and item 2 is verbosity; the description compensates for none of this gap.

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 states the verb 'Read' and names the method 'getblock' on Bitcoin, plus the chain id, but 'getblock' merely restates the tool name and no detail is given about what block data is returned. It does not differentiate from close siblings like bitcoin_getblockheader, bitcoin_getblockhash, or bitcoin_getblockcount.

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?

There is no statement of when to use this tool versus the many sibling block/transaction methods. It only gives a cost figure and a retry hint, leaving selection entirely to inference.

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