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

With no annotations provided, the description carries the full burden. It discloses the use of a public API (no auth), the parsing of subreddit/post id from publishedUrl, idempotency (unless force:true), and the side effect of auto-creating next-move actions based on outcome. This is comprehensive behavioral disclosure.

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?

Four sentences, each earning its place. The description is front-loaded with purpose, then usage condition, then mechanism and side effects, ending with idempotency. No fluff or repetition.

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?

The description covers the API endpoint, data pulled, side effects, and idempotency. It does not describe the return format, but since it writes to metadata.proof and there is no output schema, this is a minor gap. The presence of a sibling measure_hacker_news tool is not explicitly addressed, but the Reddit specificity is clear.

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%, so baseline is 3. The description adds meaning beyond the schema by explaining how actionId's publishedUrl is used to derive subreddit and post id, and clarifies the force parameter's effect on idempotency. This extra context justifies a score above baseline.

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 pulls a Reddit post's score, comments, upvote ratio, and top replies, and writes them to metadata.proof. This specific verb+resource combination distinguishes it from sibling tools like measure_hacker_news.

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 specifies when to use it: 'USE WHEN a published Reddit action is ripe for 24h measurement.' This is clear contextual guidance. However, it does not explicitly mention alternatives or when not to use it (e.g., for Hacker News posts), so it only partially meets the 'vs alternatives' criterion.

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