Render frames from an animated video project as a single contact sheet to verify style consistency and check text readability after each edit.
Render frames and return them as one sheet. Do this after every change and compare with the target frame: does it still look like the style, can the text be read on a phone?
| Name | Required | Description | Default |
|---|---|---|---|
| times | No | Seconds; default is start, middle, end | |
| project | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The readOnlyHint=false annotation already signals a non-read-only operation. The description adds that it renders frames into a single sheet for iterative visual QA, but it does not disclose side effects such as whether files are written, where the sheet is stored, or what project state changes occur.
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 sentences, front-loaded with the core action and followed by actionable usage guidance. The rhetorical questions are slightly informal but still purposeful and do not waste space.
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 two-parameter tool with no output schema, the description conveys the output shape ('one sheet') and iterative QA context. However, it omits parameter meaning and side-effect details that an agent would need to invoke it confidently.
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 only 50%, with the required 'project' parameter undocumented in both schema and description. The description adds no meaning about what 'project' identifies or how 'times' maps to rendered frames, leaving parameter semantics under-specified.
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 and resource: 'Render frames and return them as one sheet.' The 'one sheet' output form helps distinguish it from the generic render sibling, though it does not explicitly name alternatives such as preview or render.
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?
It gives a clear triggering condition ('after every change') and concrete evaluation criteria ('compare with the target frame', phone readability). It stops short of explicit exclusions or naming when to use preview, render, or check_video instead.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.