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

Annotations only declare readOnlyHint and openWorldHint, but the description adds real behavioral detail: the return shape {courseId, version, blocks}, savedAt for older revisions, that version 0 with no blocks means nothing has been written, that a nonexistent version is a not-found error, and that content_set saves a new version rather than erasing history.

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 core action is front-loaded and every subsequent clause (sibling routing, return shape, error cases, set/rollback workflow) carries distinct information with no filler. It is dense and runs long as a single block, which slightly hurts scannability, but nothing is redundant.

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?

There is no output schema, so the description carries the return-value burden and does so fully by naming the returned fields and the savedAt variant. Combined with error semantics and version handling, an agent has everything needed to call and interpret this reliably.

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 baseline is 3, and the description adds semantic value beyond the schema: `version` selects an older saved revision, must come from course_version_list, and omitting it yields the current version, with explicit error behavior for a missing version. The `id` parameter gets no additional meaning, keeping it short of a 5.

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 ('Get a course's lessons as EditorJS blocks') and immediately clarifies the domain structure (H2 headers are sections, H3 are units). It explicitly contrasts itself against siblings course_get and fetch, so an agent can select correctly without opening any 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 when-to-use routing: use this for authoring source, course_version_list to list revisions, course_get for settings, fetch for catalog summary. It also states a concrete workflow prerequisite — read the current version before course_content_set to preserve block ids — and describes the rollback procedure.

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