List Alpaca API Endpoints

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

The description reinforces the read-only nature already indicated by annotations and adds useful behavioral boundaries: it operates on one allowed spec and excludes Broker API. It does not explain the output structure, but the output schema exists and the annotations cover the safety profile, so the added contextual value is meaningful.

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?

Two sentences carry the full purpose, usage context, read-only status, exclusions, and an alternative tool reference with no wasted words. The primary action and scope are front-loaded.

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 metadata-browsing tool with one optional parameter, an output schema, and annotations covering read-only behavior, the description is complete. It tells the agent what the tool does, when to use it, what scope limitations exist, and which sibling to prefer for targeted lookup.

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% and there are no enums, but the description compensates by naming the three allowed API areas: Trading API, Market Data API, and Authentication API. This gives the agent a clear sense of what the 'title' parameter should contain, even though the description does not explicitly map the parameter to those values or mention the 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 tool lists endpoints for a single Alpaca OpenAPI spec inventory, specifically distinguishing Trading API, Market Data API, and Authentication API while excluding Broker API. This is a specific verb+resource combination that differentiates it from related search and documentation tools.

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 says when to use the tool ('when browsing the available endpoint inventory... before narrowing to a specific endpoint') and names the preferred alternative for targeted lookup ('prefer search_alpaca_api_specs'). It also provides an exclusion (Broker API), giving clear routing guidance.

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