Update asset metadata

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

Annotations already declare non-destructive, idempotent, open-world behavior. The description adds the upsert semantics ('Update or add'), which is useful beyond the annotations, but it says nothing about permissions, error handling, or what happens to existing keys not included in the request.

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 short and front-loads the action. The first line duplicates the title, and the operation/tag metadata line is marginally useful, but there is no significant bloat.

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?

With annotations covering safety and idempotency, a fully documented schema, and no output schema, the description provides enough to call the tool correctly. Remaining gaps (error cases, response shape) are minor for a simple metadata upsert.

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 baseline is 3. The description's mention of 'key-value pairs' aligns with the schema's items array but adds no syntax, format, or constraint details beyond what the schema already documents.

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 ('Update or add') and resource ('metadata key-value pairs') plus scope ('for the specified asset'), which implicitly distinguishes it from the bulk sibling immich_update_bulk_asset_metadata. However, it does not name that sibling explicitly, so sibling differentiation is only implicit.

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 explicit when-to-use guidance, no alternatives named, and no prerequisites mentioned. The phrase 'Update or add' clarifies the operation's effect but does not help an agent decide between this tool and the bulk metadata update sibling or other asset-update tools.

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