List scenes in the account

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

Beyond the readOnlyHint annotation, the description discloses meaningful behavior: results are sorted newest first, it reports which scan_ids are new since the last list, and the account is positioned as a sync layer. This gives the agent useful expectations that are not present in the schema or annotations.

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 three compact sentences: main purpose, key behavioral detail, and next-step guidance. Every sentence adds value and the most important information comes first.

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 read-only listing tool with one optional, fully documented parameter and no output schema, the description covers the essential behavior and the sync context. It does not describe the exact shape of the returned scene list, but it gives enough for an agent to invoke correctly and follow up with scene_card.

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%, and the parameter since_epoch_s is already clearly described in the schema as 'Only return scenes created at/after this epoch-seconds timestamp'. The tool description does not add extra meaning about the parameter, so the baseline of 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?

States a specific verb ('List') and resource ('all persisted scenes in the signed-in Open Reality account'), with an ordering detail ('newest first'). This clearly differentiates it from scene-specific tools like scene_card or scene_list_objects.

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 explains when this tool is relevant: persisted scenes in the account, with the account acting as a sync layer for scans from phone or web. It also gives an explicit next step ('Use scene_card next for anything you want context on'), though it does not exhaustively contrast with every sibling.

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