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

No annotations are present, so the description carries the burden for behavioral disclosure. It does disclose a maximum result count and per-call credit cost, but it omits pagination behavior, auth requirements, and response shape.

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 text is short and front-loaded with the main action, and the cost/limit information is included in a compact second sentence. However, the phrasing 'Max - 100 Billing per call: 1 Credits' is awkwardly packed.

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, no annotations, and 3 unrequired parameters, the description is too sparse to support confident autonomous use. It doesn't explain how to identify the target user, how pagination flows through next_max_id, or what the response contains.

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?

The schema covers id_user and next_max_id (67%) with brief descriptions, but the query parameter is undocumented and the description adds no clarification about how query vs id_user should be used. The agent is left guessing which parameter is needed for a basic lookup.

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 core function with a specific verb and resource: 'Get instagram user followers.' This distinguishes it from siblings like get_followings by naming followers, though it doesn't explicitly contrast behavior or alternative lookup methods.

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?

No guidance is given for when to use this tool versus alternatives such as get_followings or get_user_id. The note about max 100 and 1-credit billing is a limit/cost detail, not a usage guideline.

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