Read contract (eth_call)

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clearly disclosed. The description adds useful context about accepted network identifiers and an example signature. However, it does not mention the return value shape (e.g., decoded result) or what happens on revert, which would add value beyond annotations. No contradiction with annotations.

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 two concise sentences. The first front-loads the purpose and includes an example, the second lists network options. It is efficient and well-structured, though the network enumeration is slightly verbose and could be streamlined.

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 should hint at the return format (e.g., decoded return value of the function) and failure behavior (e.g., reverts). It only covers input specification, leaving the agent unaware of the response shape or error handling. For a tool with 4 parameters and non-trivial call semantics, this is a noticeable gap.

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% with clear descriptions for address, signature, args, and network. The description adds an example of the signature format and notes 'big numbers as decimal strings' for args (also present in schema). It does not introduce new meaning beyond the schema, so the baseline of 3 is appropriate.

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 clearly states the specific action: 'Call a read-only (view/pure) contract function' and provides an example signature format. It distinguishes from sibling tools like avax_get_balance (which reads a known balance) or avax_get_code (which reads code) by focusing on arbitrary contract function calls. However, it does not explicitly name a sibling to avoid confusion, so it's not a 5.

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 description explains how to provide the signature, args, and network, but does not explicitly compare this tool with alternatives or state when not to use it. It implies usage for read-only contract calls for any EVM contract, leaving the agent to infer that other tools like get_balance are for specific predefined reads. No exclusions or conditional guidance is given.

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