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

Annotations already declare destructive/openWorld/non-idempotent, and the description adds the value that annotations cannot: which command classes require user approval, which execute immediately, and which need background execution with a follow-up job_output call. That is real behavioral context beyond the structured hints.

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 front-loaded sentences, each earning its place: invocation form, approval gating, then background/job_output handling. No filler and no repetition of the title.

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 compensates by explaining the background + job_output flow and the approval_id follow-up pattern, so the async return path is covered. Minor gaps remain around error/permission behavior, but the agent has what it needs to call the tool correctly.

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 67%, and the description supplements the undocumented `args` (shape/examples) and `background` (which slow commands warrant it) parameters. It doesn't touch `why`, `site`, `server`, or `approval_id`, but those carry schema descriptions, so the added meaning over the schema is meaningful without being complete.

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 (run bin/magento as the site's owner in its root) and backs it with two concrete argument examples, so an agent immediately knows this executes Magento's own CLI. It does not explicitly distinguish itself from the generic `run` or `wp` siblings, which keeps it short of a 5.

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 clear operational context: status commands run straight away, while uninstalls/rollbacks/admin user changes/URL-head-script config need approval, and it routes slow commands to `background` plus `job_output`. It stops short of telling the agent when to pick this over the generic `run` or `wp` tools.

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