Bulk subscribe

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

Annotations cover the safety profile (not read-only, idempotent, non-destructive). The description adds meaningful behavioral context beyond them: the consent requirement, the 1000-contact ceiling, and that it returns a job id to poll asynchronously via plunk_get_bulk_job_status.

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?

Bolded labels (Purpose, Not for, Returns, Use when) front-load the key facts. Every sentence earns its place; no filler.

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 single-param async bulk mutation with no output schema, the description supplies the async follow-up (poll job status), consent constraint, and limit. Nothing essential is missing.

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?

Only one parameter with 0% schema description coverage, so the description must compensate. It indicates the parameter is a list of existing contacts with a 1000-item limit, but adds nothing about UUID format or behavior on invalid/ineligible ids.

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 (subscribe), resource (contacts), scope (bulk, up to 1000 existing contacts), and effect (opt back in to marketing email). Clearly distinguishes from the sibling plunk_bulk_unsubscribe_contacts and plunk_subscribe_contact.

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?

Has explicit 'Use when' (correcting mistaken mass unsubscribe, migrating consent) and 'Not for' (reversing self-chosen unsubscribes) guidance, giving both positive and negative selection criteria.

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