unifi_protect_get_event_thumbnails

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

Beyond the readOnlyHint annotation, the description discloses token cost per image, a hard cap of 6, and the non-failing behavior for events without thumbnails. This is significant context that an agent needs to predict cost and handle partial results correctly.

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?

The description is front-loaded with the main purpose and each subsequent sentence adds decision-relevant guidance: use case, sibling preference, cost/cap, and failure behavior. No sentence is wasted.

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 two-parameter read-only tool with no output schema, this description covers when to use it, how to select inputs, cost implications, and what happens when thumbnails are missing. Nothing essential is left out.

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 100%, so the input schema already documents both parameters, including the eventIds cap and the output enum. The description reinforces the cap and the inline-return intent but does not add substantial parameter semantics beyond the schema. Baseline 3 is appropriate.

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 first sentence states a specific verb and resource ('Fetch the still frames for SEVERAL events at once') and highlights that frames are returned inline. It also clearly distinguishes this batch tool from the singular unifi_protect_get_event_thumbnail sibling.

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?

The description explicitly says to prefer this tool over calling unifi_protect_get_event_thumbnail repeatedly, and tells the agent to pick worthwhile events from unifi_protect_list_events instead of scanning a whole night. It also explains the key use case: identifying who or what was there when smart detection is unavailable.

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