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list_cameras

Discover available cameras: Lists all detected physical USB webcams and IP cameras with ID, name, resolution, fps, and state. Refresh to rescan for newly plugged devices.

Instructions

List all detected physical USB webcams and IP cameras with their ID, name, resolution, fps, and state.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
refreshNoIf true, rescans USB bus and PNP devices for newly plugged cameras.

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

A3.5/5.0
Behavior3/5

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

With no annotations, the description carries the full burden. It discloses the returned field set (ID, name, resolution, fps, state), which usefully signals a read-only enumeration, but it says nothing about permissions, whether discovery is cached, or how long a scan takes. Adequate but with clear gaps.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single front-loaded sentence with zero padding, and the returned fields are placed after the core action. Efficient, though the field enumeration is the only elaboration.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a one-optional-param read tool with no output schema, stating the returned fields plus the refresh rescan in the schema is nearly sufficient. Missing only behavioral notes such as permission requirements or scan latency.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, and the only parameter (refresh) is fully documented in the schema as triggering a USB/PNP rescan. The description mentions no parameters, so baseline 3 applies — the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('List all detected physical USB webcams and IP cameras') and even enumerates the returned fields, so the agent knows exactly what this produces. It is clear without opening the schema, though it does not explicitly contrast itself with siblings like get_status or set_camera_settings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied rather than stated: listing cameras is self-evidently the way to discover device IDs before calling set_camera_settings or capture_image, but the description never says when to use this over alternatives. No exclusions or prerequisites are given.

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