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

No annotations are provided, so the description must carry the full behavioral burden. It only says 'number discarded,' which is not enough for a 9-parameter tool; it omits whether parameters are independent, what checks are performed, side effects, return behavior, and failure modes.

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 very short, but the brevity reflects under-specification rather than tight communication. It is not front-loaded with actionable purpose, and the four words do not earn their place because they misdirect the agent.

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 tool with 9 optional parameters, no annotations, no output schema, and a highly varied parameter set, the description is completely inadequate. It omits purpose, usage, behavior, and relationship to siblings, leaving an agent unable to select or invoke the tool correctly.

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 description coverage is 100%, so the schema already documents each parameter fully (e.g., ref discarded after shape check, path no disk access, zone IANA timezone). The description adds nothing useful about parameters and is unrelated to them, but the high schema coverage establishes a baseline of 3.

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 'Grains to grams, number discarded' does not describe the tool's actual schema, which spans Git refs, URLs, weather hints, RSS feeds, hosts, JSON, file paths, timezones, and search queries. It is misleading rather than merely vague: an agent would expect a unit-conversion tool, not a multi-purpose shape/validation utility.

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?

There is no guidance on when to use grain-g versus any sibling such as validate-json, iana-zones, weather-hint, file-path-ok, or search-query-len. The description provides no context, prerequisites, or exclusions.

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