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

Annotations already declare this is a non-read-only, idempotent, non-destructive, closed-world write, so the safety profile is covered. The description adds the useful 'Part of Premium' gating fact, which is not in the annotations. It does not disclose what happens when toggled off (e.g., whether quoting reverts to a single default UPI ID) or any side effects on existing supports, so behavioral coverage is partial.

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 compact sentences with no filler, and the conditional 'When on' leads so the reader immediately anchors on the toggle state. The metaphor about support 'landing in one account' is slightly wordy but earns its place by clarifying the rotation concept. No structural waste.

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?

An output schema exists, so return values need not be explained, and the Premium gate is surfaced. Missing pieces are the effect of disabling rotation, the relationship to set_default_upi_id, and whether the change affects in-flight or pending supports. For a simple boolean toggle this is adequate but leaves meaningful behavioral questions unanswered.

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% for the single 'enabled' boolean, so the description must carry the meaning. 'When on, active UPI IDs take turns...' does imply what the boolean controls, giving partial compensation, but it never names or contrasts the on/off states explicitly. Baseline 3 is appropriate for a one-param tool where the description only indirectly conveys the flag's semantics.

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 explains the semantics of the resource (active UPI IDs taking turns being quoted so support spreads across accounts), which pairs with the name set_upi_rotation and the title to convey that this toggles that rotation behavior. It distinguishes itself from sibling UPI tools like set_default_upi_id by describing a rotation concept rather than a default selection. However, it never states the action in verb form (enable/disable rotation), leaving the tool's operation implied rather than explicit.

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?

The description gives no guidance on when to enable rotation versus using set_default_upi_id or other UPI siblings, and no exclusions. The only contextual signal is 'Part of Premium', which is a prerequisite, not usage routing. An agent must guess the appropriate scenario from the feature description alone.

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