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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds real value by disclosing the returned payload (source/target forms, state, context, location, flags, labels, explanation, suggestion/comment flags, web link) and the underlying GET endpoint, though timestamps, auth or rate-limit behavior are not mentioned.

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?

A single front-loaded sentence with the identity and payload, plus the endpoint suffix. The field enumeration is a bit list-like but each item conveys what the agent will receive, so little 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?

With no output schema, the description usefully compensates by listing the fields returned, which is the main thing an agent needs to decide whether this call supplies the data it wants. Only usage routing is missing, and that is minor for a one-parameter read.

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 schema already explains that unit_id is a Weblate unit id from weblate_list_units. The description only restates 'by id' and adds no format or lookup detail, so the baseline of 3 applies.

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 ('One string by id') and enumerates what the returned unit contains, which separates it from the plural weblate_list_units. It does not name the sibling tool explicitly, so differentiation is implied rather than stated.

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 when-to-use guidance or mention of when to prefer weblate_list_units or a search instead. The only hint that the id comes from a listing tool lives in the schema, not the description.

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