instagram_comments

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds real value beyond them: it enumerates the returned fields (author, text, time, likes, reply count, total count), flags that only 'top' comments come back, and discloses a cost of 3 credits. It stops short of saying how many comments constitute 'top' or whether pagination exists.

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?

Two tight sentences plus a one-line cost note; the core purpose and the returned fields are front-loaded with zero filler. Every clause carries information an agent can act on.

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 correctly compensates by listing the return fields and the total count, which is enough to judge whether to call it. The remaining gap is the volume/limit semantics of 'top comments' and any pagination behavior.

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 schema already explains the url/shortcode alternation ('Pass this or shortcode'), so parameter documentation is fully handled elsewhere. The description adds no parameter-level meaning, which is the expected baseline when the schema does the heavy lifting.

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 ('Get comments on an Instagram post') and further narrows scope to 'the top comments... plus the total comment count.' An agent can distinguish it from a generic post-fetch tool, though it never names its closest sibling (instagram_comment_replies) to disambiguate the two comment-reading tools.

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 only implied by the scoping phrase 'top comments' and by the sibling list; there is no explicit statement of when to pick this over instagram_comment_replies or instagram_post, and no prerequisites or exclusions given. The agent must infer the boundary.

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