plunk_subscribe_contact

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

With no annotations, the description carries the disclosure burden. It adds critical behavioral context about the correct id type (public id embedded in unsubscribe links, not UUID), which is essential for correct invocation. However, it does not mention side effects like idempotency or error conditions, so it's not fully transparent but still informative.

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 sentences with no redundancy. The primary action and the key distinction (public id vs UUID) are front-loaded, and the alternative is mentioned concisely.

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?

The tool is simple with one parameter and no output schema. The description covers the purpose, the critical id distinction, and the alternative for batch. It doesn't mention potential idempotency or response, but for a straightforward subscribe operation, this is sufficient. It is reasonably complete given the tool's simplicity.

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 schema already provides 100% coverage of the single parameter, including a detailed description of the public id and how to obtain it. The description adds no new parameter semantics beyond what the schema already states, so it meets the baseline for high schema coverage.

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 subscribes a contact via their public id, which is specific and distinct from other sibling tools like plunk_create_contact or plunk_unsubscribe_contact. It also explicitly notes the id type (public, not UUID) and references the batch alternative, making the purpose unambiguous.

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 explicitly directs users to use plunk_bulk_subscribe_contacts for batch subscribes by regular id, providing clear when-to-use guidance. It also implies this tool is for a single subscribe using the public id, effectively distinguishing it from bulk operations.

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