list_modal_apps

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

No annotations provided, so the description carries the burden. It discloses the tool lists deployed/running or recently stopped apps, and returns a parsed JSON list. No side effects or limitations mentioned, but the basic behavior is clear.

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: one sentence for purpose, one for usage hint, followed by clearly separated Args and Returns sections. No superfluous text, front-loaded with key information.

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?

Given the simple tool (one optional parameter) and the presence of an output schema (context indicates true), the description adequately covers purpose, usage, parameter details, and return format. No obvious gaps.

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 0%, but the description thoroughly explains the 'env' parameter: it's optional, targets a Modal environment, and defaults to the profile's default or MODAL_ENVIRONMENT variable. This adds significant meaning beyond the schema's type and default.

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 ('List'), resource ('Modal apps'), and scope ('currently deployed/running or recently stopped'). It effectively distinguishes from sibling tools that focus on secrets, volumes, containers, etc.

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 explicitly mentions the tool is 'useful for discovering the app name or ID to pass to other app tools', providing context. It does not state when not to use or explicitly name alternatives, but the sibling list implies differentiation.

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