Set Student Assignment Dates

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

Given destructiveHint=true, the description adds essential behavioral detail: partial failures are tolerated, one Canvas API call per assignment, V1 is create-only and already-existing overrides return 422 and appear in failed[], and not_found handling for nonexistent assignment IDs. The pseudonymization prerequisite (resolve_pseudonym first) is also disclosed. No contradiction with annotations.

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 description is long but dense: each sentence covers a distinct concern (operation, failure tolerance, API call volume, create-only limitation, audit prerequisite, date format, return envelope, pseudonym note). It is front-loaded with the core purpose and then structured into operational details, though a bit verbose.

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?

With no output schema, the description fully explains the return envelope (applied[], skipped[], failed[], not_found, summary) and the meaning of each array. It also covers failure semantics, prerequisites, pseudonymization, and performance implications. This is complete given the tool's complexity and the absence of an output schema.

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 the schema already documents each parameter. The description adds value by clarifying real-world semantics: 'Provide user_id as the real Canvas user ID', 'Dates must be ISO 8601 strings', and that omitting assignment_ids targets all assignments while nonexistent IDs go to not_found. This goes beyond the schema without fully re-explaining every field.

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 opens with a specific verb and resource: 'Fan a due-date / availability override for a specific student across all (or a filtered subset of) assignments in a course.' This clearly distinguishes it from siblings like set_student_quiz_accommodation (quiz-specific) and create_assignment_override (single assignment).

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 tells the agent when to audit first ('Use list_assignment_overrides to audit first'), explains the create-only constraint with a concrete 422 failure mode, and provides a workflow for relative date shifts ('first call list_assignments with include=overrides to retrieve current dates, compute absolute timestamps, then call this tool'). This is strong usage guidance beyond simply naming alternatives.

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