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

No annotations are provided, so the description carries the full burden. It discloses credit cost per action and the supported network matrix, plus the caveat that credits are indicative and returned in headers, which is genuinely useful. However it omits auth requirements, rate limits, and read-only nature.

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?

Purpose and action list are front-loaded, but the credits block repeats six near-identical lines with the same values for every action, which is pure redundancy. The network matrix earns its place; the credits enumeration largely does not.

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 nine-parameter tool with 100% schema coverage and no output schema, the description supplies the action inventory, supported blockchain/network combinations, and cost signal an agent needs. Only pagination behavior and error semantics are left unaddressed.

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 description coverage is 100%, so the schema already documents all nine parameters including required blockHash/blockHeight conditions. The description adds nothing beyond mapping action names to their intent, so baseline 3 applies.

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 and resource ('Get EVM block details') and enumerates all six actions the tool can perform. The 'EVM' qualifier cleanly distinguishes it from siblings like block_data__utxo_block_data and block_data__xrp_block_data.

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 action list implies which action to pick for which need (by height vs by hash, single vs list), but there is no explicit when-to-use guidance, no prerequisites, and no routing to alternative siblings. Usage is inferable from action names only.

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