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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds important behavioral context beyond annotations: values are archive data that may be approximate or update hours/days late, and the range must not exceed 1,000 points. It does not mention authentication or rate limits, but for a read-only data tool the added data-quality caveat is meaningful.

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 three tightly written sentences. The core purpose is front-loaded, constraints follow, and the final sentence routes away to alternatives, with no redundant or filler content.

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?

Given that an output schema exists, annotations cover safety, and the input schema is fully documented, the description provides everything an agent needs: the exact resource, metric options, precision/bounds constraints, data-quality caveats, and sibling tool routing. No critical information is missing.

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 all five parameters are already documented in the schema. The description reinforces that metric and precision must be 'documented' and that created_after/created_before are absolute bounds, but it does not add syntax, format details, or other meaning beyond the schema 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 uses a specific verb ('Get') and precisely names the resource: Arctic Shift's native historical time series for Reddit post/comment counts, score sums, retrieval-delay sums, and subreddit subscribers. It explicitly distinguishes itself from sibling tools reddit_archive_posts_search and reddit_trends, so an agent can identify its role without inspecting schemas.

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?

It gives clear when-to-use guidance, including required selection of a documented metric and precision, absolute created_after/created_before bounds, and a maximum range of 1,000 points. It also names the alternative tools and their purposes: reddit_archive_posts_search for individual posts and reddit_trends for current feed rankings.

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