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

The annotations already disclose that this is destructive but idempotent, so the description adds useful context about consequences: dates return to the shared pool and the weekly cap, the text key is deleted, and turns revert to the shared model. It also states the return shape as { removed }, which is helpful because there is no output schema. It does not discuss authentication requirements or edge cases around existing texts.

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 description is short and front-loads the key consequences: free usage, date-cap restoration, key deletion, and model reversion. Every sentence contributes useful information and the return value is stated tersely.

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?

Given rich annotations, a single optional parameter fully covered by the schema, and no output schema, the description is complete enough to call the tool correctly. It explains the important side effects and even compensates for the missing output schema by naming the returned field.

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?

There is only one optional parameter, agent_id, and the schema already describes it as optional within a session with 100% description coverage. The description adds no parameter-level meaning beyond the schema, so the baseline of 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?

The description states a specific action and resource: deleting the user's text key to remove their BYOK setup and revert to the shared model. It also spells out the consequences for dates and turns, which makes the tool's purpose clear. It does not explicitly name the sibling alternative such as set_model, so it falls short of full sibling differentiation.

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 implied by the description: this is the tool to use when the user wants to stop using their own key and return to the free shared model. However, there is no explicit "use this when" guidance, no exclusions, and no direct comparison to set_model or my_model.

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