Avanza 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 and does well by detailing what information is returned (e.g., NAV, performance, risk metrics, fees, characteristics) and implying a read-only operation without destructive effects. However, it lacks explicit mention of rate limits, authentication needs, or error handling, leaving some behavioral aspects uncovered.

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 well-structured and front-loaded, starting with the core purpose, followed by details, usage guidelines, args, returns, and an example. Every sentence adds value without redundancy, making it efficient and easy to parse for an AI agent.

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 (1 parameter, no annotations, but with an output schema), the description is largely complete: it covers purpose, usage, parameters, and return details. However, it could improve by explicitly stating it's a read-only operation or addressing potential errors, though the output schema mitigates some gaps.

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 input schema has 0% description coverage, but the description compensates by explaining that 'instrument_id' is an 'Avanza fund ID from search results,' adding crucial context beyond the schema's type definition. It also includes an example usage, though it doesn't detail format constraints or validation rules.

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 detailed information') and resource ('about a mutual fund'), distinguishing it from siblings like get_fund_chart, get_fund_holdings, or get_fund_description by emphasizing comprehensive data including NAV, performance, risk metrics, fees, and characteristics.

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?

It explicitly provides when-to-use guidance by directing users to 'Use search_instruments() with instrument_type="fund" to find fund IDs,' and distinguishes from alternatives by specifying this tool is for detailed fund info, not charts, holdings, or descriptions, making it clear when to choose this over sibling tools.

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