ig_use_account

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

The annotations declare readOnlyHint=true (no state modification), while the description's only content is that it *changes* the active account - a stateful side effect. That is a direct tension between the text and the structured safety hint, and no other behavioral context (scope of the switch, persistence, effect on subsequent calls) is given.

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?

A single short, front-loaded sentence with no filler or repetition. It is efficient, though brevity here shades into under-specification, which is penalized in the other dimensions rather than this one.

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?

For a tool with one required, undocumented parameter and no output schema, the description should at minimum say what the account switch affects and what happens on success/failure. Instead it supplies only the bare action, leaving the agent unable to invoke it correctly with confidence.

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 0% and the single required parameter 'username' is undocumented in the schema. The description never mentions that an account identifier must be supplied or what form it takes (handle vs. numeric ID), so it fails to compensate for the coverage gap.

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 names a specific verb ('Cambia') and resource ('la cuenta activa'), so an agent can tell it is an account-switching tool rather than a listing or posting tool. It does not, however, distinguish itself from siblings like ig_accounts or ig_profile, which is exactly the gap that keeps this at a 4 rather than a 5.

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?

There is no statement of when to use this tool versus ig_accounts/ig_profile, nor any prerequisite such as needing to know the target username first. The usage is only weakly implied by the word 'activa', which is not enough guidance for an agent choosing among 24 sibling tools.

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