update_asset_metadata

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

With no annotations provided, the description carries the full disclosure burden and delivers: 'permanently changes asset metadata in Immich' warns of the irreversible side effect, 'Only provided fields are modified' clarifies partial-update semantics, and the rating caveat ('cannot be cleared from here, 0 is not a rating Immich 3.x accepts') flags version-specific behavior.

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?

Purpose, use cases, and side effect are front-loaded in three tight sentences; the Args list maps 1:1 to schema parameters in a scannable format; the single Returns line closes the contract. Every sentence earns its place given 7 parameters need documentation.

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 7-parameter mutation tool with no annotations and no schema-level descriptions, the description covers purpose, when to use it, side effects, every parameter's format and range, and the return shape (backed by the output schema). Nothing an agent needs to construct a correct call is missing.

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%, and the description fully compensates by documenting all 7 parameters with real semantics: UUID for asset_id, an ISO 8601 example for date_time_original, decimal-degree ranges for latitude/longitude, and the -1/1-5 rating scale with rejection semantics that the bare schema could never convey.

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 and resource: 'Update metadata fields on a specific asset.' The singular framing distinguishes it from the sibling update_assets_metadata, and the concrete use cases (fix dates, correct GPS, add descriptions, change favorite/rating) make the tool's scope unmistakable.

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?

Provides explicit when-to-use context via 'Use this to fix dates, correct GPS, add descriptions, or change favorite/rating status.' However, it does not name the batch alternative update_assets_metadata or state when not to use this tool, so it stops short of full when/when-not routing.

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