List app files

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

The description goes beyond readOnlyHint=true by disclosing pagination mechanics ('limit/cursor page through'), prefix narrowing, and that it returns a page plus usage totals rather than a flat list. 'Renders no UI' is a genuinely useful behavioral exclusion. Annotations already cover the read-only safety profile, so the description adds meaningful behavior context without contradicting them.

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?

Three terse, information-dense sentences with the core purpose and return shape front-loaded, followed by only the details that disambiguate it from siblings. No filler; every clause earns its place.

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 read-only list tool with a 100%-documented schema, a true output schema, and safety annotations, the description is nearly complete: it covers return fields, paging, filtering, and file-type semantics. Minor gaps remain — behavior for a nonexistent app, permission requirements, and explicit differentiation from file_read — so it falls just short of a 5.

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 100%, so all four parameters are already documented individually. The description adds only the relational framing that limit/cursor form a paging mechanism and prefix narrows, which is mildly useful but largely redundant with the schema's own notes (e.g., 'opaque cursor from the previous page's next_cursor'). Baseline 3 is appropriate.

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 ('List') and resource (the files an app has stored), and names the return shape ({path, size, mime, version} plus usage totals), distinguishing it at a glance from data_list. It also clarifies what the files are (opaque user files like attachments/exports) and what the tool is not ('Renders no UI').

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?

Provides clear context: 'These are opaque user files... separate from its structured data collection' implicitly routes structured-data queries to the data_* siblings. It stops short of explicitly naming alternatives or stating when not to use it, so it is contextual rather than fully prescriptive.

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