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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds useful behavioral context: the tool returns a complete outline with study guide slugs and gives a token-cost estimate. This goes beyond the structured annotations without contradicting them.

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?

Three front-loaded sentences, each earning its place: what it returns, how it is used, and cost considerations. No filler or repetition of schema fields.

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?

Given the rich annotations and presence of an output schema, the description is sufficiently complete for selecting and invoking the tool. It covers scope, purpose, and cost. It could have explicitly contrasted itself with get_unit_overview, but the schema already provides subject resolution guidance, so nothing critical 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 the schema already documents both intent and subjectSlug, including examples and the suggestion to use list_subjects. The description adds no parameter-specific semantics, but the baseline of 3 is appropriate because the schema carries the full burden.

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 names a specific action (returns the full unit and topic outline) and a resource (one AP subject), and distinguishes it from siblings like get_unit_overview and get_study_guide by emphasizing the complete course map and study guide slugs. It is clear what this tool produces and how it differs from adjacent tools.

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 implies clear usage context: use it for study planning and to locate individual study guide slugs before retrieving guides. It does not explicitly name alternatives or exclusions, but the stated use cases are specific enough to route an agent appropriately among the sibling tools.

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