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

Annotations only give generic hints (readOnlyHint=false, idempotentHint=true); the description adds concrete context the annotations cannot: a fixed 0.005 USDC cost on Base mainnet and the requirement to preserve the idempotencyKey for retries. This meaningfully explains the paid-call and retry behavior, though it does not say what happens if the key is reused incorrectly or what the response looks like.

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 short sentences, each front-loaded and free of filler; cost and idempotency guidance appear immediately. The opening clause is somewhat tautological with the method name, but the chain identifier makes it earn its place.

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 read-only RPC wrapper with no output schema, the description covers cost and retry semantics but omits the shape of the params tuple and what data is returned. An agent knows how to pay but not fully how to construct the call.

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 only 50%: the idempotencyKey is documented in the schema itself, and the description merely repeats that ('Preserve the private idempotencyKey for retries'). The three-element params array (txid hex, const verbose=false, blockhash) is undocumented in both schema and description, so the description fails to compensate for the coverage 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 names a specific verb (Read) and resource (getrawtransaction) and pins the network with the bip122 genesis identifier, so an agent can tell it apart from the ethereum_* siblings and the other bitcoin_* tools. It is clear, though 'Read getrawtransaction' partly restates the tool name rather than describing the resource in plain terms (a raw transaction by txid).

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 alternatives such as bitcoin_gettxout or the block-oriented siblings. The only operational guidance is about payment and retries, which is not tool-selection guidance.

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