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

Annotations cover the read-only/non-destructive safety profile. The description adds real behavioral context beyond that: it reads live from Instagram rather than a cached copy, covers one account at a time, and discloses the null-vs-zero follower edge case. It also carves out explicitly what it does NOT return (per-post views/reach/saves). Loses a point only for not describing error/rate-limit behavior on a live external call.

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?

Front-loads the purpose well, but it is a long run-on collection of clauses. The sibling contrast, null behavior, exclusion of per-post stats, and the aside about the reports screen all share one unwieldy sentence. Information is valuable but could be structured more tightly.

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?

No output schema and only one param, so the description carries the return-shape burden and does so by naming the returned fields, the null edge case, and the explicit exclusion of per-post stats. An agent has enough to call it correctly and interpret the result; only error-path detail is absent.

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% and the single parameter is already fully documented in the schema, including the default-first-account behavior and the reference to account_instagram_accounts. The description adds no parameter detail beyond the schema, so baseline 3 applies.

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+resource: fetches the live Instagram profile of a connected account, and explicitly enumerates the returned fields (handle, display name, follower count, profile picture URL). It distinguishes itself from the sibling account_instagram_accounts by contrasting live-from-Instagram vs stored copy.

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?

Gives concrete when-to-use triggers ('how many followers do I have', 'whose account is this', 'wants the picture', handle may have changed since connection) and names the alternative tool with the condition that selects it. Also states the explicit scope limit of one account at a time.

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