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 effectively describes what the tool returns (market status, timing information) and the specific data structure. It doesn't mention rate limits, authentication needs, or error conditions, but provides clear behavioral context about the information returned.

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 with a clear purpose statement, followed by bullet-point details of what it provides, parameter explanation, return value structure, and a practical example. Every sentence earns its place, and information is front-loaded with the core functionality stated first.

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, no annotations, and the presence of an output schema (implied by the detailed return structure in the description), the description is complete enough. It explains what the tool does, what parameter it needs, what it returns, and provides an example - covering all essential aspects for a read-only informational tool.

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 has 0% description coverage, but the description compensates well by explaining that 'instrument_id' is an 'Avanza instrument ID from search results'. This adds crucial semantic context beyond the schema's basic string type. The description doesn't provide format examples or validation rules, but gives meaningful usage guidance.

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 marketplace status and trading hours') and identifies the resource ('for an instrument'). It distinguishes this from sibling tools like get_stock_info or get_stock_quote by focusing specifically on market operational status rather than pricing, analysis, or company 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 'instrument ID from search results' and provides an example for checking market openness. However, it doesn't explicitly state when to use this tool versus alternatives like get_stock_info (which might include market status) or when not to use it. No explicit alternatives or exclusions are provided.

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