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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds that data comes from live on-chain RPC and that it validates rather than merely fetches, plus the input-safety constraint about secrets — useful, but it says nothing about failure behavior (e.g., what happens if no readkey is registered).

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 short sentences with the core action and source front-loaded, followed by a single safety caveat. No filler or redundancy.

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 rich annotations and an output schema present, the description only needs to convey the action, source, and input constraints — all of which it does. The one gap is reasoning about validation failure or missing-registration outcomes, which slightly limits an agent's ability to anticipate errors.

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% and the single walletAddress parameter is already documented with a regex pattern and a description of its signer/starter/actor role. The description adds no additional meaning about that parameter, so the baseline 3 applies.

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?

Specific verb pair (read/validate), specific resource (a wallet's PUBLIC P-256 readkey), and a specific source (XRC-563 via live XGR RPC). This clearly separates it from neighbors like get_xrc729_authority or list_xgr_grants_for_readkey, which handle different resources.

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 the use case (fetch and verify a registered readkey for a wallet) but never states when to prefer this over alternatives such as list_xgr_grants_for_readkey or get_xrc_contract, nor any prerequisites like a prior registration. 'No private keys or secrets are accepted' hints at a constraint but is phrased as a warning, not a routing rule.

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