canvas_enroll_user

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

With no annotations, the description carries the full behavioral burden and does well: it warns the roster is mutated, clarifies the default invite-and-accept flow versus direct activation, and explains that no email is sent unless notify is requested. It stops short of stating auth/permission requirements or idempotency/reversibility of enrollment.

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 purpose and mutation warning are front-loaded, then defaults, then per-argument detail. It is somewhat long, but each sentence adds usable information and there is 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 mutation tool with no annotations and an output schema already present, the description supplies the missing safety/behavior context and full parameter semantics. An agent has everything needed to invoke it correctly.

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 0%, so the description must compensate and it does: every one of the six parameters is documented with meaning, including the 'sis_user_id:ABC123' alternate format, the allowed enrollment_type values, the invited/active distinction, and the env-var default for course_id.

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 and resource ('Enrol a user in the course') and immediately flags the side-effect profile ('MUTATES the roster'), which cleanly separates it from the read-only siblings like canvas_list_enrollments and canvas_list_students.

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?

Explains the default behavior (state=invited, notify=False) and tells the agent when to deviate ('Pass enrollment_state="active" to place them straight onto the roster'). It also gives real-world context for SIS ids, but never explicitly names an alternative tool or states when NOT to use it.

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