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

Annotations already mark this as read-only and non-destructive, and the description adds useful behavioral context: it returns only the header 'without the full block body' and provides the output shape. This is sufficient for a simple read-only RPC call, though it doesn't mention error behavior.

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?

The description is compact and well-structured with clear sections: main action, when to call, input requirements, and output. Every sentence contributes either selection guidance, invocation constraints, or expected result, with no filler.

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 single-parameter read-only lookup with no output schema, the description fully covers what the agent needs: the exact hash format, the reason to prefer this tool over alternatives, and the return shape. No critical context is missing.

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 baseline is 3. The description adds value by emphasizing the critical exact 64-hex-character requirement and by giving a practical example of where such a hash comes from (e.g., tx confirmation), which goes beyond the schema's terse 'Block top hash (hex)'.

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 opens with a specific verb-object pair: 'Get a block header by its 64-char hex hash', which precisely states the tool's action and resource. It also distinguishes this tool from sibling dero_get_block by explicitly noting that this variant excludes the full block body.

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 'When to call' section gives explicit guidance: call when you have a block hash and only need the header. It also names an alternative, dero_get_block, for when transactions or miner_tx are needed, making the selection criteria clear.

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