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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=false, so the safety profile is covered. The description adds one useful constraint — fields are validated against the type's declared shape — but says nothing about partial-update behavior, required permissions, or what happens to unspecified fields on update.

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?

Two short sentences, purpose front-loaded, zero filler. Slightly under-informative for a nested-object mutation tool, but nothing 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 three-required-param mutation with a nested 'fields' object and no output schema, the description is adequate but thin. It omits how to discover valid content types, error behavior on schema mismatch, and update-vs-create semantics — gaps the annotations don't cover either.

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%: 'handle' is documented ('Lower case, dashes for spaces') while 'type' and 'fields' are bare. The description helps slightly by implying 'fields' must match the type declaration, but it never explains what 'type' refers to (a content-type handle vs. a display name), leaving a required parameter ambiguous in both schema and description.

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 pair (create or update) and a specific resource (one entry of a custom content type), with an illustrative example ('for example a banner'). It distinguishes itself from list_content_types and get_page by being the write path, though it never names a sibling explicitly.

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 or when-not-to-use guidance. It doesn't say the caller must first know the type's declared shape (e.g. via list_content_types), nor what happens if the handle already exists — the 'upsert' name implies overwrite-on-match but that is not explained.

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