alpaca-mcp-server

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

Annotations provide readOnlyHint=true and openWorldHint=true, but the description adds valuable behavioral context beyond this. It explains authentication constraints ('Paper/free accounts must set feed="iex" to avoid 403 errors'), data source options with implications, and the automatic computation of start time. This enhances the agent's understanding of operational nuances.

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 efficiently structured: a clear purpose statement followed by a bullet-point-like explanation of parameters. Every sentence earns its place by providing essential information without redundancy. It's appropriately sized for the tool's complexity and easy to parse.

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 tool's complexity (11 parameters, 0% schema coverage), the description provides comprehensive coverage of inputs, usage notes, and constraints. With an output schema present, it appropriately focuses on input semantics and behavioral context rather than return values. It leaves no significant gaps for agent understanding.

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?

With 0% schema description coverage, the description fully compensates by providing detailed semantics for all 11 parameters. It explains each parameter's purpose, format (e.g., 'comma-separated tickers', 'RFC 3339'), default values, constraints (e.g., '1–10000'), and practical implications (e.g., feed choices affecting access). This adds substantial value beyond the bare schema.

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 specific action ('Retrieve historical bid/ask quotes'), resource ('for one or more stocks'), and scope ('level 1'), distinguishing it from siblings like get_stock_bars or get_stock_latest_quote. It precisely communicates what the tool does without ambiguity.

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 provides clear context for when to use certain parameters (e.g., 'Paper/free accounts must set feed="iex" to avoid 403 errors') and explains default behaviors (e.g., start computation when omitted). However, it lacks explicit guidance on when to use this tool versus alternatives like get_stock_bars or get_stock_latest_quote, which would be helpful for sibling differentiation.

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