Pay: subscriptions relink

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

Annotations already flag destructiveHint=true and readOnlyHint=false, but the description goes well beyond them: it says all existing user links are replaced, the previous user loses access, Stripe/Apple billing is unchanged, and it is reversible by relinking back. It also warns to confirm with the user before running.

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?

Purpose is front-loaded, but the first two sentences restate each other ('Move a subscription to another user (project admin). Project-admin tool that moves a subscription to another project user...'), which is redundant. The remainder is useful and earns its place, but the opening repeats.

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 destructive, admin-only mutation with no output schema, the description covers effects, permissions, reversibility, and billing side effects well. It stops short of covering return values or error behavior, but the conceptual picture needed to invoke it safely is largely complete.

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 coverage is 100%, so both parameters are already documented ('Subscription id (guid)' and 'User id to move the subscription to'). The description adds 'numeric user id' and 'another project user', which slightly reinforces the target semantics but does not meaningfully extend the schema. Baseline 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?

States a specific verb (move/relink) and resource (subscription to another user), plus scope (project-admin tool). It also clarifies the mechanism ('replacing all its existing user links'), which separates it from siblings like pay_subscriptions_resync or pay_subscriptions_list without opening their schemas.

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?

Gives a clear use case ('to fix a purchase bound to the wrong account'), a prerequisite (project admin), and an undo path ('relinking it back'). It does not explicitly name or exclude alternatives such as resync, but the context for when to reach for it is unambiguous.

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