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

With no annotations, the description carries the burden; 'Read' implies a non-mutating operation, and it discloses that output is decoded as uint and address. It says nothing about behavior for nonexistent slots, chain/block defaults, or error conditions on unsupported 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?

Two compact clauses, front-loaded with the core action and immediately followed by the decoding behavior and use cases. 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?

An output schema exists so return values need not be explained, and the purpose is covered. However, a 4-parameter tool with zero schema descriptions leaves the agent guessing about slot encoding and chain/block selection, which are exactly the details that cause failed calls.

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 0% across 4 parameters, so the description must compensate and largely does not. It implies 'address' (contract) and 'slot' but never states slot format (hex vs decimal, full 32-byte vs truncated) or that chain and block are selectable and default to ethereum/latest.

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 ('Read a raw storage slot of any contract') and anchors it to the underlying RPC method (eth_getStorageAt), plus the decoded representations returned. This is clearly distinguishable from higher-level siblings like read_contract or decode_calldata.

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?

Gives concrete when-to-use cases: proxy implementation slots, packed variables, and debugging. It does not explicitly exclude alternatives (e.g. 'for ABI-level reads use read_contract instead'), so an agent must infer the boundary, but the context is strong.

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