Navigate the device browser back one entry in its session history (history.back()) — works on BOTH iOS Safari and Android Chrome.
| Name | Required | Description | Default |
|---|---|---|---|
| udid | Yes | Device UDID / serial (iOS or Android) | |
| pageId | No | Target page/tab id — auto-picked when omitted | |
| socket | No | Android only: abstract unix socket name (default: chrome_devtools_remote) | |
| platformVersion | No | Ignored (kept for compatibility) |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the behavioral disclosure burden. It notes the operation wraps history.back() and is cross-platform, which is useful. However, it doesn't disclose edge-case behaviors such as what happens when history is empty (no-op vs error), whether the operation fails silently, or if it requires a currently-open page context. For a navigation operation, moderate additional context would be valuable.
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, zero waste. The first sentence states the purpose precisely, and the second adds cross-platform scope. Every word serves a function.
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 relatively simple navigation action with 100% schema coverage and a single required parameter, the description is adequately complete. It doesn't address return value or empty-history behavior, but for a straightforward browser-navigation tool with good schema documentation, this is near-complete. Slightly more on failure behavior would fully close the gap.
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%, so parameters are already well-documented. The description adds value by framing the tool's main requirement (udid) implicitly and noting the platform scope, but it doesn't add meaning about parameters beyond what the schema provides. The 'platformVersion' parameter is described as 'Ignored (kept for compatibility)' in the schema itself, so the description doesn't need to add more.
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?
The description clearly states the verb+resource: 'Navigate the device browser back one entry in its session history (history.back())'. It specifies the exact underlying mechanism (history.back()) and confirms cross-platform support for both iOS Safari and Android Chrome. It's unambiguous and distinguishes from related navigation tools like webpage_forward, webpage_reload, and device_navigate_url.
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 notes it 'works on BOTH iOS Safari and Android Chrome', giving clear platform context. However, it doesn't explain when one would choose this over sibling tools like device_get_browser_url or session_back, nor does it mention when not to use it (e.g., if no history exists). It provides clear context but no explicit exclusions or alternative naming.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
The set contains near-identical duplicate families: web_* and playwright_* expose ~15 pairs of the same desktop-grid-browser operations (web_get_text/playwright_get_text, web_reload/playwright_reload), and screenshot/log/network/mock capabilities each have 5-8 entry points (device_screenshot vs android_mjpeg_screenshot vs ios_screenshot vs ios_fast_screenshot vs web_screenshot vs webpage_screenshot vs session_screenshot). Many individual descriptions carefully draw boundaries (devtools vs traffic, HID vs session), but an agent cannot reliably distinguish web_* from playwright_*, and ios_screenshot/ios_fast_screenshot/ios_mjpeg_screenshot blur together.
The prefix scheme is broken: Android functionality is split arbitrarily between android_* and device_* (device_screenshot vs android_mjpeg_screenshot), the desktop browser gets two parallel prefixes (web_* and playwright_*), and verbs vary across equivalents (device_navigate_url vs web_navigate vs ios_safari_navigate). session_* uses bare verbs (session_url, session_back), and the same concept gets different names (ios_clipboard_get_hid vs ios_get_pasteboard; device_screen vs ios_orientation).
333 tools is an extreme count by any measure — far beyond the 50+ threshold — and much of the bulk is duplicative (the web_*/playwright_* pairs alone double ~15 slots) or out-of-scope for a device-control server (TestRail, Jira, AzDO, agent memory, secret variables, feedback). Even granting that remote device control + test automation is a broad domain, this surface will devastate agent context budgets and is impossible to navigate coherently.
The core device-control and test-automation domain is remarkably thorough: Android and iOS each have full interaction, app-lifecycle, file, network/proxy, performance, crash, accessibility, recording, and replay coverage, with CRUD lifecycles for flows, suites, app uploads, TestRail cases, and visual-review baselines. Minor gaps exist at the margins — Jira/AzDO lack update/transition/comment operations, and iOS cannot open/close tabs — but the central workflows have no dead ends.
