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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the absence of safety disclaimers is acceptable. The description adds useful behavioral context beyond annotations by detailing what the timeline contains (crawl snapshots with dates, item counts, content hash) and the optional aggregation behavior when course is omitted, which is valuable for predicting outputs.

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 concise and well-structured: a single clear purpose sentence, followed by a compact Args list and a Returns line. No fluff or redundancy; every sentence contributes essential information.

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?

No output schema exists, so the description must convey return value expectations; the 'Returns' line provides a high-level summary (timeline of snapshots and changes). It covers the required parameters, optional behavior, and primary output, but could be more explicit about the structure or sorting of the timeline. Still, for a read-only history tool with good annotations, it is sufficiently complete.

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 the input schema already documents each parameter's meaning and constraints. The description repeats the parameter details without adding new semantics; the only slight addition is reiterating that omitting course returns history for all courses, which is already in the schema. Baseline of 3 is 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?

The description uses a specific verb ('Show') and clearly identifies the resource ('crawl history and change timeline for a specific course'), distinguishing it from sibling tools like get_curriculum_changes by emphasizing crawl snapshots and content hashes. It also scopes the operation via subject/grade/course parameters.

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?

No explicit guidance on when to use this tool versus alternatives such as get_curriculum_changes or get_course_curriculum. The description only implies usage by describing its functionality and notes optional course omission, but does not state when one should choose this over siblings.

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