capture

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

With no annotations, the description carries the full burden and does disclose meaningful traits: clamped output size (longest edge 64..1024), aspect-ratio source, and that viewport capture is interactive-only. It does not state whether the call is read-only/non-destructive, whether it blocks during a Cycles render, or whether a file is written versus data returned.

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 dense sentences with the deliverable front-loaded and no filler. The middle clause ("scene aspect ratio: camera render or viewport (interactive only)") is slightly telegraphic and takes a second read, which keeps it off a 5.

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 3-param tool with no annotations and no output schema, the description adequately covers output format and all three parameters. Gaps remain around preconditions (interactive session, existing scene/render context) and response shape, which the missing output schema leaves undocumented.

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 0%, so the description has to compensate and largely does: it explains the size clamp (longest edge 64..1024), the two view behaviors (camera render vs viewport, interactive only), and the engine default/alternative. It still omits the literal enum values and units, leaving minor guesswork.

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?

Leads with the concrete deliverable ("PNG preview") and adds the render-pipeline details that make the intent unambiguous — an agent knows this produces a snapshot image rather than inspecting or executing code. It never names the sibling tools, but inspect/discover/execute are generic enough that the resource (a rendered preview) still separates it.

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?

Gives parameter-level tradeoff guidance (EEVEE is the fast default, pass engine="CYCLES" for ray-traced quality), which implies when to reach for the heavier path. It says nothing about when to choose capture over the sibling tools or what state must exist before calling it.

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