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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, openWorldHint=true, so the safety profile is covered. The description adds the meaningful behavioral trait that this call blocks until the condition is met rather than returning immediately, but it does not say what happens on timeout (error vs. silent return), which is the main behavioral unknown for a wait primitive.

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 sentences, front-loaded with the core action and its condition set, then the routing constraint. Every clause earns its place and nothing is repeated from the schema.

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 an output schema absent but all five params documented in the schema and annotations covering the safety profile, the description supplies what the structured fields cannot: the desktop-vs-device scoping and sibling routing. The only omission is timeout failure behavior, a minor gap for a wait tool.

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 100% and each parameter carries its own description (text, state enum, pageId provenance, selector, timeoutMs default), so the schema does the heavy lifting and baseline 3 applies. The description only reinforces the pageId scoping to the desktop grid browser; it adds no format or syntax detail beyond the schema.

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 (wait for) on a specific resource (the DESKTOP grid browser, addressed by pageId) and enumerates the three condition families it supports: element appear/disappear, text, or fixed delay. It also explicitly distinguishes itself from two siblings, web_evaluate (polling) and webpage_wait_for (device), so an agent can route without opening another schema.

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 an explicit alternative ('Prefer this over polling with web_evaluate') and an explicit exclusion ('Not a device — for a phone or tablet use webpage_wait_for (by udid)'), covering both when to use and when not to use it.

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