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

With no annotations, the description carries the full burden, and it does disclose the key behavioral trait that omitting parameters returns the current chain-tip block. It does not cover error behavior, what happens if both height and blockhash are supplied, or costs/limits, so it is only adequate.

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?

A single front-loaded sentence: resource and returned fields first, then default behavior, then usage triggers in a bracketed clause. Nothing is wasted and the most important information comes first.

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 two-optional-parameter read tool with no output schema, the description covers the returned fields, the default resolution rule, and use cases. Remaining gaps (mutual-exclusivity handling, error cases) are minor but present.

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%, so the parameters are documented in the schema itself. The description adds the defaulting behavior when no parameter is passed, which the schema does not state, giving it a slight edge over the baseline of 3.

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 (查询/query) and resource (比特币区块摘要) and enumerates exactly what the summary contains: transaction count, size, weight, block time, confirmations. This clearly separates it from siblings like btc_mempool_summary and btc_tx_lookup.

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 【何时用】 section gives concrete usage triggers with example questions ('latest block tx count', 'overview of a height or hash'), and it explains the no-argument default. It stops short of naming an alternative tool or a when-not-to-use case, but context is clear.

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