Lists mp4 and jpg files in the NVR export directory with name, size, and modification time. Read-only, so you can inspect exported footage without altering anything.
List mp4/jpg files in the export directory (name, bytes, mtime). Read-only.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the full behavioral burden. It discloses read-only status and the return fields, but says nothing about auth requirements, directory scoping, rate limits, or whether the listing is paginated.
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 short, front-loaded sentences with no waste. The output fields are grouped parenthetically and 'Read-only' is appended compactly, though the very terse style leaves room for a bit more useful context.
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, parameterless listing tool with an output schema already covering return values, the description is nearly sufficient. It could still note auth or directory constraints, but nothing essential to correct invocation is missing.
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?
The tool takes zero parameters, so there is no parameter semantics to explain; the baseline for a parameterless tool is 4. The description's mention of name/bytes/mtime pertains to output rather than inputs.
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 ('List mp4/jpg files in the export directory') and even names the returned fields (name, bytes, mtime). It is clear what the tool does, but it does not differentiate itself from siblings like nvr_get_export or nvr_list_recording_segments.
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?
No when-to-use guidance, no prerequisites, and no mention of alternatives such as nvr_get_export. The only hint is 'Read-only', which speaks to behavior, not to when this tool should be selected over its siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.