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

Annotations already establish that the tool is read-only, non-destructive, and idempotent, reducing the burden on the description. The description adds value by enumerating the returned metadata fields, which is a useful behavioral context beyond simple safety flags. However, it does not disclose any additional traits such as error handling, rate limits, or network dependencies, so it remains at the baseline for annotation-backed descriptions.

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 a single, efficient sentence that front-loads the purpose and lists concrete outputs without redundant words. Every word contributes meaning, making it an excellent example of concise tool documentation.

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 simple read-only tool with one parameter and no output schema, the description is largely complete: it specifies the input, the kind of data fetched, and explicitly lists the expected return fields (which substitutes for a missing output schema). However, it omits any note about error behavior (e.g., unknown rune names) which could be helpful, though not strictly necessary given the tool's straightforward nature.

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 input schema provides complete documentation for the sole parameter 'name', including case-insensitivity, automatic spacer stripping, and an example ('DOG•GO•TO•THE•MOON' or 'DOGGOTOTHEMOON'). With 100% schema description coverage, the description itself need not add further detail. This matches the baseline of 3 for high schema coverage.

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 starts with a specific verb ('Fetch') and identifies the resource ('protocol-level metadata for a Rune token by name'), then explicitly lists the fields returned (ID, supply, divisibility, symbol, premine, etching transaction, lock height). This clearly distinguishes it from sibling tools like getRuneBalances or getRuneMarketInfo which target different aspects of Rune data.

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 fetching Rune metadata by name, but it provides no explicit guidance on when to use this tool versus alternatives (e.g., getRuneBalances, getRuneMarketInfo) or any exclusions. With multiple Rune-related sibling tools, a brief note about which scenarios call for this tool would strengthen the score.

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