immich-mcp

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

Annotations provide 'idempotentHint: true', indicating safe retries, which the description doesn't repeat—this is good. However, the description adds minimal behavioral context beyond the annotations: it implies a mutation (updating) but doesn't disclose permissions needed, error conditions, or what happens if 'name' or 'color' are set to null. With annotations covering idempotency, the description adds some value but lacks depth on other behavioral traits.

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 a single, efficient sentence that directly states the tool's function without unnecessary words. It's front-loaded with the core action ('Update'), making it easy to parse. Every word earns its place, and there's no redundancy or fluff, achieving optimal conciseness.

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?

Given the tool's moderate complexity (a mutation with 3 parameters) and lack of output schema, the description is minimally adequate. It covers the basic action and parameters but misses key context: no output details, no error handling, and incomplete parameter guidance. Annotations help with idempotency, but the description doesn't fully compensate for the gaps in schema coverage and missing output information.

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 low (33%), with only 'tag_id' documented in the schema. The description mentions 'name or color', which aligns with two of the three parameters, adding some semantic meaning beyond the schema. However, it doesn't explain the optional nature of 'name' and 'color' (they can be null) or provide format details (e.g., color codes), leaving gaps. Baseline is 3 as the description partially compensates for low schema coverage.

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 clearly states the action ('Update') and the resource ('a tag's name or color'), making the purpose immediately understandable. It distinguishes this tool from sibling tools like 'immich.tags.create' or 'immich.tags.delete' by focusing on modification rather than creation or removal. However, it doesn't specify what 'tag' refers to in the context of the Immich system, which slightly limits specificity.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an existing tag ID), exclusions (e.g., when not to update), or comparisons to sibling tools like 'immich.tags.create' for new tags or 'immich.tags.get' for viewing. This leaves the agent without context for tool selection in a workflow.

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