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

The description adds real behavioral context beyond the destructiveHint annotation: it grants access, records a manual enrollment at a given price, explicitly does NOT charge the learner's card, and optionally emails the learner. It omits auth/permission needs and idempotency (behavior when the user is already enrolled), so it is strong but not complete.

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 compact sentences, front-loaded with the 'WRITE:' signal and the operation, followed by the behavioral caveats and endpoint. 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 an 8-parameter mutation tool with no output schema and only a destructiveHint annotation, the description covers the essential behaviors an agent needs (access grant, price recording, no charging, optional email). It lacks any statement about already-enrolled behavior or response shape, keeping it from a 5.

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 description coverage is 88%, so the schema already documents nearly every parameter. The description reinforces price semantics ('use 0 for a free grant') and the no-charge rule, but adds little else beyond what the schema states, making the baseline 3 appropriate.

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+resource with the exact scope: 'manually enroll a user in a course, bundle or subscription'. The 'WRITE:' prefix and manual-enrollment framing clearly separate it from read siblings like get_user_course_progress or list_user_courses, and from learnworlds_add_user_to_group.

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 clear context for when this is the right tool (manual enrollment, no card charge, 'use 0 for a free grant') and implies the learner-facing purchase path is different. It does not name a sibling alternative or state an explicit when-not, so it stops short of a 5.

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