Set axis values

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

Annotations are minimal (readOnlyHint=false, destructiveHint=false), so the description carries most of the behavioral burden. It discloses upsert-by-id semantics, repeatability, no count cap, verbatim sections from user materials, and exactly what hide_nav does to navigation and chips. It does not cover auth or errors, but the core mutation behavior is clear.

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 front-loaded and uses a compact pseudo-schema, but it contains a duplicated rationale sentence near the end and some domain jargon. It could be tightened without losing meaning.

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?

The description is rich in domain context: it explains the consent-gate timing, why this tool exists, the entity-axis contrast, and hide_nav behavior. Still, it leaves label and singular undefined, and with no output schema it does not mention what the agent should expect in return. An agent would still need to guess on required parameters.

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?

With 0% schema description coverage, the description must compensate, and it does for some parameters: values gets a full inline shape, slot is constrained to 1 or 2, and hide_nav is explained in detail. But required parameters timeline_id, label, and singular receive no explanation, leaving significant gaps for a 6-parameter tool with 5 required parameters.

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: 'Define or extend an extra axis (slot 1 or 2) after the consent gate.' It also distinguishes this tool from the entity axis and from axes declared inside create_timeline, so an agent can tell what it is for and how it differs from siblings.

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 gives clear when-to-use context: after the consent gate, repeatedly as material arrives, and whenever the axis belongs to a course's cases. It also gives a concrete heuristic for hide_nav. However, it never explicitly names an alternative tool or states when not to use this one, so it stops short of a 5.

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