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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds that it surfaces live status and block height, which implies a live network read, but says nothing about auth needs, freshness, or failure behavior for unknown chains.

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 that names the resource first and then lists the returned fields. No filler, no redundancy, nothing that could be cut without losing information.

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?

With no output schema, the description usefully enumerates the returned fields, which is exactly the gap it should fill for a read-only lookup tool. Minor omissions remain (error behavior on an unrecognized chain, what 'live status' values mean), keeping it short of a 5.

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?

Only one parameter and schema description coverage is 100%; the schema already explains that chain accepts a slug, name, or chain ID with concrete examples. The description adds no syntax or matching-precedence detail beyond that, 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 resource (one chain) and enumerates exactly what it returns: chain ID, live status, block height, and HTTP/WebSocket/archive endpoint URL templates. The phrase 'One chain' implicitly separates it from list_chains, though the sibling is not named explicitly.

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 when-to-use or when-not-to-use guidance, and no alternatives are named. An agent must infer from 'One chain' that this is the single-chain lookup versus list_chains, but nothing tells it when the endpoint detail here is preferable to probe_endpoint or rpc_call.

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