alpaca-mcp-server

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

Annotations provide readOnlyHint=true and openWorldHint=true, indicating safe read operations with flexible inputs. The description adds valuable behavioral context beyond annotations: it explains automatic start time computation when omitted, default values for lookback parameters, and data point limits across symbols. No contradiction with annotations.

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 concise explanation of automatic start computation, then a well-organized Args section. Every sentence adds value with no redundancy or fluff.

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 (9 parameters, historical data retrieval), the description is complete: it covers purpose, parameter semantics, behavioral details, and usage context. With an output schema present, return values don't need explanation, and annotations cover safety aspects.

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 9 parameters: it explains symbols format, timeframe options, start/end behavior, lookback defaults, limit range, and sort options. This adds crucial meaning 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 price bars') and resource ('cryptocurrencies'), distinguishing it from sibling tools like get_crypto_latest_bar (real-time) or get_stock_bars (different asset class). It explicitly mentions OHLCV data, providing precise scope.

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 this tool (historical data retrieval) and implies when not to use it (for real-time data, use get_crypto_latest_bar). However, it doesn't explicitly name alternatives or state exclusions, though the sibling list shows related tools.

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