What To Do Now

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description goes further by disclosing the composition of the result set (unfinished/due-soon, overdue, not-yet-open, quizzes needing double-check, already submitted), which is genuinely useful behavioral context given there is no output schema. It stops short of noting pagination, ordering guarantees, or result caps, so it is not a 5.

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, zero waste: the resource plus bucket enumeration comes first, the usage trigger second, and the sibling routing last. Every clause earns its place and the most important information is front-loaded.

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 read-only query tool with full schema coverage and no output schema, the description supplies everything needed: what it returns (the bucket composition), when to call it, and when to call a sibling instead. Nothing an agent needs in order to select and invoke it correctly 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?

Schema description coverage is 100%, so both parameters (daysAhead, includeOverdueDays) are already documented with defaults and bounds. The description implies the concepts of 'due soon' and 'recently overdue' but adds no format, units, or interaction details beyond what the schema provides. Baseline 3 applies when the schema does the heavy lifting.

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 resource (prioritized to-do list) and scopes it precisely across all courses, then enumerates the five buckets it contains (due soon, overdue, not open yet, quizzes to double-check, already submitted). It explicitly names the sibling it is not, so an agent can distinguish it from get_upcoming_due_dates without opening either schema.

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 explicit selection criteria: 'Use this first when the user asks what to work on, what's left, or what they should do now.' It also names the alternative and the condition that selects it ('For a plain chronological list of deadlines or a custom date range, use get_upcoming_due_dates instead'), leaving nothing to inference.

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