Read a contract storage slot

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

Annotations already mark the operation read-only and open-world; the description adds useful context by naming eth_getStorageAt and specifying the return shape: a 32-byte word plus uint and address interpretations. It does not discuss block defaulting or edge cases, but it meaningfully extends the annotation-only information.

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 a single front-loaded sentence: the first clause names the action, resource, and RPC method, and the second specifies the return format. There is no filler or redundant restatement of the tool name.

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 read-only storage getter with two required parameters, the description plus schema provides the essential information: address, slot, chain, RPC override, and the expected return values. The main missing context is the semantics of the optional block parameter and explicit guidance on sibling alternatives, but these are relatively minor gaps.

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?

The schema documents slot, chain, and rpc_url, but address and block have no descriptions. The description does not clarify the ambiguous block parameter or add per-parameter meaning; it mainly reinforces the operation-level behavior. With 60% schema coverage, this is adequate but leaves gaps unaddressed.

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 states a specific operation ('Read a raw storage slot via eth_getStorageAt') and identifies the resource as contract storage. It distinguishes itself from siblings like get_bytecode or eth_call by emphasizing raw storage and naming the exact RPC method.

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 explicit guidance on when to use read_storage versus compute_storage_slot, eth_call, or get_bytecode. The description does not mention alternatives, exclusions, or conditions, so the agent must infer usage from the sibling list and tool name.

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