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 of behavioral disclosure. It adequately describes what the tool returns (comprehensive ESG metrics) but doesn't mention potential limitations like rate limits, authentication requirements, error conditions, or whether the data is real-time versus cached. It provides functional context but lacks operational transparency.

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 with clear sections (purpose, usage guidance, args, returns, examples) and front-loaded information. While slightly verbose in listing all return metrics, each sentence adds value, and the example is practical. Minor trimming of the returns list could improve conciseness.

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 (single parameter, no annotations, but with output schema), the description is reasonably complete. It covers purpose, prerequisites, parameter semantics, and return values in detail. The presence of an output schema reduces the need to fully document returns, but the description still provides helpful context about the metrics structure.

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 description adds significant meaning beyond the input schema, which has 0% description coverage. It explains that 'instrument_id' is an 'Avanza fund ID from search results' and provides an example value ('41567'), clarifying the parameter's purpose and format. For a single parameter with no schema documentation, this compensation is substantial.

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 fund sustainability and ESG metrics') and resources ('fund'), distinguishing it from sibling tools like get_fund_info or get_fund_holdings by focusing exclusively on sustainability metrics rather than general information or holdings 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 provides explicit guidance on when to use this tool versus alternatives: it instructs to 'Use search_instruments() with instrument_type="fund" to find fund IDs' before invoking this tool, clearly establishing a prerequisite workflow and distinguishing it from direct search or other fund-related tools.

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