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

Annotations only supply readOnly/destructive/openWorld hints; the description adds substantial behavior beyond them: null or "" clears a field, newSlug renames the file and changes the URL (with a redirect caveat), draft=false publishes, and writes are staged as unsaved branch changes reviewed in Xodia. It also discloses validation behavior (wrong types are refused with the field and reason) and plan limits (Free: 2 collections / 100 items; paid plan to convert a folder into a collection).

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 field list is front-loaded, but the body is one dense run-on stitched together with semicolons and nested parentheses, making the locale rules hard to parse on first read. Content is largely justified, but a bulleted or split structure would preserve the same information with less parsing cost.

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 10-parameter mutation with no output schema and only hint-level annotations, the description covers the risky edges: clearing values, URL-changing renames, publishing, branch staging, locale branching, and plan limits. It stops short of saying what the tool returns (updated item? branch diff?) or what happens on slug collision, which an agent would want before calling.

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 coverage is 80%, so the baseline is 3, but the description adds genuine meaning the schema lacks: locale-specific semantics for each parameter (values translatable-only with shared fields refused, newSlug as the per-language slug, draft as that language's publish state, and publishedAt/order being locale-incompatible). The two undocumented schema params (order, publishedAt) are only touched via that exclusion and their value shape is never explained.

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?

Opens with a specific verb and resource ("Changes one item") and immediately enumerates the mutable facets: values, newSlug, draft, publishedAt, order. The locale paragraph further scopes it to writing a translation file at content/<collection>/<slug>.<code>.md, which distinguishes it from create_items, get_item, and update_collection without needing their schemas.

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?

Gives a real conditional rule for the trickiest mode ("With locale ... writes that language's translation ... Translate only when the user asks") and explains that writes land as unsaved changes on the open branch for the user to review in Xodia. It does not explicitly route to siblings (e.g. use create_items to add, get_item to read, update_collection for schema changes), so the when-not guidance is inferred rather than stated.

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