get_stream_snapshot

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

With no annotations, the description carries the full burden, and it does disclose the output format ('live JPEG snapshot frame ... as an MCP Image'), which is genuinely useful. However it says nothing about whether the stream must already be running, latency/freshness behavior, failure modes, or permissions, so meaningful behavioral gaps remain.

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?

A single well-formed sentence with the resource and return type front-loaded and no filler. It is efficient, though it is terse enough that the missing parameter and usage detail had to go somewhere.

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?

No output schema and no annotations, and two of three parameters are undocumented in both schema and description. The return type is covered, but the resize parameters and any prerequisites for capturing a live frame are missing, which is inadequate for a 3-parameter tool.

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 three parameters. The description names `stream_name`, but `width` and `height` — presumably resize dimensions — are never mentioned, so an agent gets no semantic guidance on those two parameters from either source.

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 ('Capture a live JPEG snapshot frame from `stream_name`') and even names the return type (MCP Image), which clearly separates it from siblings like get_stream_urls or probe_stream. It stops short of explicitly naming an alternative tool, so it is clear but not sibling-differentiating.

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?

There is no when-to-use or when-not-to-use guidance, and no mention of how this differs from probe_stream or get_stream_urls for inspecting a stream. The usage is only implied by the verb 'Capture'.

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