List available symbols

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

With no annotations provided, the description carries the behavioral burden. 'Lists the instruments' clearly indicates a read-only operation with no side effects, and adding the data-provenance context is useful. It does not disclose output format or potential limitations, but these are less critical for a simple listing tool.

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 one short sentence that immediately states the core function and then adds one useful contextual detail. Every word earns its place; there is no filler.

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 parameterless listing tool with no output schema, the description is reasonably complete: it tells the agent what will be listed and mentions the provenance. It could mention the exact shape of the returned data, but this is a minor gap for such a simple tool.

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?

The tool has zero parameters awaited with 100% schema coverage, so there is nothing for the description to add. Baseline 4 is appropriate given no parameter semantics are needed.

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 ('Lists'), a resource ('instruments this server can analyse'), and an additional scope ('where their data comes from'). This clearly distinguishes list_symbols from its siblings, which perform analysis, price retrieval, indicators, and position sizing.

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 implies that this tool is used to discover available symbols before calling analysis tools, but it does not explicitly state when to use this tool versus alternatives. It provides no exclusions or conditions, though the listing purpose is inherently distinct from the sibling tools.

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