Read native track curves, mass-weighted COM, and rig connection errors at every stored frame (max 121) without moving the playhead.
Read native track curves, rigid-body mass-weighted COM and rig connection errors at every stored frame (max 121). Does not move the playhead.
| Name | Required | Description | Default |
|---|---|---|---|
| character_id | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false. The description adds valuable behavioral context beyond those annotations: it discloses the data types read, the frame limit (max 121), and explicitly states that the playhead is not moved. It does not cover return format or permission requirements, but with annotation coverage the bar is lower.
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?
Two compact sentences, front-loaded with the action and data scope, followed by the key non-mutation guarantee. No filler or redundancy; every phrase earns its place.
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 no output schema, the description adequately enumerates the three categories of returned data (track curves, COM, connection errors) and the frame cap. The main missing piece is parameter guidance for character_id, which prevents a perfect score. Safety and read-only behavior are fully covered by annotations and the playhead note.
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 0% for the single required parameter character_id. The description never mentions the parameter, its meaning, or how to obtain valid IDs. The schema supplies only a UUID pattern, leaving the description to compensate but it does not, so this is a significant gap.
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 states a specific verb ('Read') and a precise set of resources (native track curves, rigid-body mass-weighted COM, rig connection errors) over a defined scope (every stored frame, max 121). It clearly distinguishes itself from pose-reading or transform tools by naming the exact inspection targets. However, it does not explicitly contrast itself with any sibling, which keeps it from a 5.
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 only guidance is 'Does not move the playhead', which hints at a safe read operation but does not state when to use this tool versus alternatives like get_character_pose, get_rig_semantics, or retime_character_motion. There is no explicit when-to-use, when-not-to-use, or alternative routing despite many sibling tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.