td_timeline

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

The description states it returns a JSON envelope with specific fields, adding value beyond annotations (which already indicate it is read-only, idempotent, and non-destructive). It does not contradict annotations and provides concrete return structure info.

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 a single sentence with no wasted words. It front-loads the action and resource, then lists the fields. Perfectly concise.

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 simple read-only tool with no parameters and an output schema present, the description adequately covers the purpose and return format. It might optionally mention error conditions or prerequisites (e.g., timeline must exist), but this is not critical.

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?

There are no parameters, so the baseline score is 4 per instructions. The description adds no parameter detail (unnecessary) but lists the fields returned in the output, which is helpful.

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 the specific verb 'Read' and identifies the resource 'current timeline state', listing specific fields (frame, seconds, FPS, playing). This clearly distinguishes it from sibling tools like td_timeline_set, which would write to the timeline.

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 usage for reading timeline state, but does not explicitly state when to use this tool versus alternatives (e.g., td_timeline_set for writing). No exclusions or contextual guidance beyond the verb 'Read'.

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