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

Annotations already declare the safety profile (not read-only, not idempotent, not destructive), so the bar is lower. The description adds two real behavioral facts not in the annotations: writes are validated against the collection schema, and the tool is plan-gated. It says nothing about what happens on validation failure, whether the row is immediately published, or quota 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?

Three terse fragments, front-loaded with the action, no filler. It is arguably under-specified rather than verbose, but nothing in the text 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?

For a mutation tool taking a nested `data` object validated against a dynamic schema, with no output schema, the description omits key operational detail: the meaning of `slug`, whether `site_id` is needed when a site is already selected, and the result of a failed validation. Given the low schema coverage, more was required here.

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 only 33% and the description only restates the `data` parameter ('field key → value, validated against the schema'). Neither `slug` (which collection? format?) nor the optional `site_id` is explained anywhere, so two of three parameters are effectively undocumented.

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?

Specific verb + resource ('Create one row'), which implicitly distinguishes it from the bulk sibling create_collection_rows. However it never names that sibling or the collection it writes into, so the singular/plural distinction must be inferred from the name alone.

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?

No when-to-use guidance and no mention of the obvious alternative create_collection_rows (or import_collection_csv) for bulk inserts. 'Plan-gated' hints at a prerequisite but is not explained as a usage condition.

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