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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the mutation/safety profile is partly covered. The description adds genuinely useful context beyond that: the payload is not generated here and the plugin pulls it during sync, which prevents the agent from assuming a file artifact is produced.

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 first sentence is well front-loaded and informative. However, the final clause ('so say that plainly rather than implying a file was produced') is meta-instruction about how to phrase things rather than tool behavior, muddying an otherwise tight definition.

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 low-complexity two-parameter mutating tool with no output schema, the description conveys the essential behavioral nuance (state change, no payload generation, plugin reads it). The only real gap is the undocumented builder/projectId parameters.

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 0%, so the description carries full burden for two parameters. It explains neither projectId nor the builder enum (elementor/gutenberg), so the agent gets no guidance on what builder selects or how the mark is scoped.

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+resource ('mark a project as exported') and clarifies what the action does ('puts it in the Exported list and what the WordPress plugin reads'). The negative clause ('does NOT generate the Elementor or Gutenberg payload') sharpens the boundary, though no sibling tool is named to route against.

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?

Implies the context in which the state matters (plugin sync reads it), but never states when to call this versus alternatives like sync_builders or publish_site, nor any prerequisites or ordering. Usage must be inferred.

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