data_sources

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

Annotations already cover read-only, idempotent, non-destructive, and closed-world behavior. The description adds important behavioral context beyond annotations: the tool requires the Stochastly desktop app to be installed and opened with an Atelier or Portfolio licence, and it describes the output field `sources`.

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 appropriately sized and front-loads the critical app/licence prerequisite, then explains output and usage. There is minor redundancy between the opening installation/licence note and the closing licence requirement, but it remains focused overall.

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 zero-parameter, read-only listing tool with no output schema, the description covers prerequisites, output content (`sources`), and its relationship to `backtest_graph`. Nothing essential for invoking the tool correctly is missing.

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?

This tool has zero parameters, so the schema does not require additional parameter semantics. The description adds no parameter meaning because there are none to explain, which aligns with the baseline for zero-parameter tools.

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 states a specific verb and resource: it lists registered data source names, names the output field `sources`, and notes that `folder` is always included. It also distinguishes the tool from `backtest_graph` by positioning it as a prerequisite for choosing that tool's `source` argument.

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?

It explicitly says to use this before `backtest_graph` to pick its `source` argument, and it states when not to rely on it: if a source is missing, pass `data_root` to `backtest_graph` instead. The prerequisite app/licence context further clarifies when the tool can be used at all.

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