Schwab MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It describes the tool's function but lacks details on behavioral traits such as rate limits, authentication needs, output format, or whether it's a read-only operation. This leaves significant gaps for an agent to understand how to interact with it effectively.

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 a single, efficient sentence that front-loads the core purpose ('Get top movers') and includes key details without waste. Every word contributes to understanding the tool's function, making it appropriately sized and well-structured.

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 moderate complexity (3 parameters with enums) and no output schema, the description is adequate but incomplete. It covers the basic purpose and parameters but lacks information on return values, error handling, or behavioral constraints, which are important for an agent to use it correctly without annotations.

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 schema description coverage is 100%, with clear descriptions for all parameters (index, direction, change) including enums and defaults. The description adds minimal value beyond the schema by summarizing the parameters ('by percent or value change'), but doesn't provide additional context or usage examples, so it meets the baseline for high schema coverage.

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's purpose with specific verbs ('Get top movers') and resources ('for an index'), specifying what kind of data it retrieves. It distinguishes itself from siblings by focusing on market movers rather than quotes, positions, or schemas, though it doesn't explicitly contrast with similar tools like query_market_data.

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 usage context by mentioning 'gainers or losers' and 'percent or value change,' suggesting when to use it for ranking market movements. However, it lacks explicit guidance on when to choose this tool over alternatives like get_quote or query_market_data, and no exclusions or prerequisites are stated.

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