probe_endpoint

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

No annotations are provided, so the description carries the full burden. It transparently states that it returns the result or error and performs the exact call, but it does not disclose potential side effects if the method is state-changing (e.g., eth_sendTransaction). This is a minor gap.

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 concise and well-structured, using two sentences to cover the tool's purpose, the two usage modes, and the expected outcome. There is no redundant or extraneous 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?

Given the tool's simplicity and the lack of an output schema, the description adequately covers what the tool does and what it returns (result or error). It lacks examples or edge-case handling, but these are not critical for such a straightforward tool.

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 already describes each parameter individually, and the description adds value by explaining the two functional modes: url-only for chain identity/block height/archive capability, and url+method+params for exact calls. This clarifies the optionality and combination of parameters beyond the schema.

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 tool's purpose: to diagnose any EVM JSON-RPC endpoint and to perform exact JSON-RPC calls. It uses specific verbs ('diagnose', 'performs') and distinguishes itself from siblings by emphasizing 'ANY' endpoint, including external ones.

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 implies usage for endpoint diagnosis and custom method calls by outlining two modes (url-only and url+method+params). However, it does not explicitly contrast with sibling tools like list_chains or get_chain, so the guidance on when to prefer this tool over alternatives is only implicit.

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