Registry Stats

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds meaningful behavioral detail beyond annotations: the exact returned fields, the sqlite path, and the fallback note behavior when the scanner has not run. 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 compact and well-organized: purpose first, then return fields, then edge-case behavior, then an example. Every sentence contributes useful information without padding 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?

For a zero-parameter read-only stats tool with an output schema present, the description is complete. It covers what the tool returns, the failure/fallback case, and the relationship to sibling tools, leaving no ambiguity for an agent deciding to invoke it.

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 tool has zero parameters, so there is no parameter schema burden to fulfill. The description still adds value by showing the example call registry_stats() and enumerating the return fields, which is plenty for a no-argument tool.

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: returning live stats from the on-chain address registry (block scanner), including specific fields like addresses_total and scanned_up_to_height. It distinguishes itself from the market/trader sibling tools by domain, though it does not name a specific sibling tool for direct comparison.

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 gives useful when-to-use context: it explains that registry stats come from the scanner, and if the scanner hasn't run, a note is returned instead while market/trader tools still work via the public indexer. This effectively guides an agent toward alternatives in the degraded case, though it could be more explicit about naming specific alternative tools.

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