prufa_upgrade_plan

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

No annotations provided, so the description bears full responsibility. It discloses that the tool is mutating and idempotent, describes the return value, and notes the agent's role restriction. However, it lacks details on side effects (e.g., what happens if already subscribed) or dependencies (e.g., workspace setup).

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 extremely concise: three sentences with no redundancy. Each sentence adds critical information: purpose, human action requirement, and behavioral characteristics (mutating, idempotent, trial).

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 no output schema, the description adequately explains the return value ('Stripe checkout_url'). It covers the trial, idempotency, and agent limitation. It could mention error scenarios or prerequisites, but the tool is simple enough that this level of detail suffices.

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 input schema has 100% description coverage, so the baseline is 3. The description does not add meaningful parameter information beyond the schema; it only lists the tier options already in the enum. The idempotency_key behavior is already well-described in the schema.

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 tool's purpose: 'Subscribe or upgrade this workspace to a paid plan' and lists the specific tiers ('starter | pro | team'). It distinguishes itself from sibling billing tools like prufa_billing_portal (manage existing) and prufa_buy_credits (purchase credits) by focusing on plan subscription/upgrade.

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 provides explicit guidance: the agent never enters card details and returns a Stripe checkout URL for the human to open. It describes the trial period and idempotency behavior. It could be improved by noting when not to use (e.g., if workspace already on a plan), but the context is clear enough.

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