previous_app

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

No annotations are provided, so the description must fully disclose behavior. It only states the action and parameter, omitting important details such as whether the loop wraps around or what happens if there is no previous app.

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 description is concise with two sentences, front-loading the primary action. It is appropriately sized with no wasted words, though minor overhead from the 'Args:' line could be trimmed.

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 simple navigation tool without an output schema provided, the description covers the action and parameter adequately. It lacks mention of loop edge-case behavior but is otherwise complete.

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%, but the description explains the clock_index parameter (optional, 0-based, defaults to first clock), adding meaning beyond the raw schema definition.

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 action ('Switch to the previous app'), the resource ('app'), and the context ('in the display loop'). This distinguishes it from sibling tools like 'next_app' and 'switch_to_app'.

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 provides context for usage (switching apps in a loop) and mentions the optional clock_index parameter, but does not explicitly state when to use this tool versus alternatives like 'next_app' or 'switch_to_app'.

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