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

With no annotations at all, the description carries the full behavioral burden. It does add genuine value by disclosing the observable effect — a banner renders on the device and is tappable by the agent — which is the key behavioral trait for a simulation tool. It omits whether delivery is synchronous, whether the notification persists in the notification center, and what happens on failure or a stale session.

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?

One front-loaded sentence with a clear action and a concrete observable result; every clause earns its place and nothing is padded.

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?

A 4-parameter mutation-ish tool with zero annotations, no output schema, a nested free-form object, and 25% schema coverage needs considerably more: session prerequisites, what `data` carries, and expected post-send state. The description covers only the surface effect, leaving the payload contract and failure behavior undocumented.

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 25% — only `session` is described ("Session from open_app"). The description says nothing about `title`, `body`, or the nested free-form `data` object, so an agent gets no guidance on payload conventions or what `data` is for. With low coverage the description was the only place to compensate, and it did not.

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?

Names a specific verb and resource ("deliver a push notification") plus the target ("the simulated phone"), so intent is unambiguous. However, it never distinguishes this from the sibling `notifications` or `open_notification` tools, leaving the agent to guess which one creates vs. reads vs. opens a notification.

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?

The description implies the scenario (triggering a simulated notification banner the agent can then tap) but gives no explicit conditions, no prerequisites beyond the schema's `session` field, and no statement of when to prefer `notifications`/`open_notification` instead. Usage is inferable from the stated outcome rather than spelled out.

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