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

Goes well beyond the readOnlyHint/openWorldHint annotations: it discloses the three-bucket result shape, that `users` is normalized to unified Creators while `hashtags`/`places` keep Instagram's native shape, that there is exactly one page with no cursor, and that a call costs 1 credit. Those are exactly the operational facts an agent needs before invoking.

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 short sentences, front-loaded with the purpose, then results shape, then pagination limit, then cost. Every sentence carries information, though the backticked field names make it slightly denser than necessary for a three-parameter tool.

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?

With no output schema, the description does the right job of describing the return buckets and their normalization. The no-cursor/one-page limit and credit cost are covered; only `cache_max_age` is left unexplained, which is a minor gap.

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 67%, so the enum on `type` and the `query` description already do much of the work. The description adds interpretive value by explaining the shape of each bucket, but never ties the `type` filter to those buckets, and `cache_max_age` is undocumented in both schema and description.

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?

States a specific verb and resource ("Search accounts, hashtags and places") and frames it as Instagram's blended search box, which implicitly separates it from single-surface siblings like instagram_profileSearch or instagram_hashtagPosts. It never names those alternatives, so the differentiation is left partly to inference.

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?

Usage is implied by the blended-search framing and the note that results come back in three buckets, but there is no explicit statement of when to use this versus the narrower sibling search tools (profile search, hashtag posts, reels search). No exclusions or prerequisites are given.

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