MCP J-Link Server

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

With no annotations provided, the description carries full burden and does well by disclosing key behavioral traits: it enumerates connected probes, returns serial numbers and product names, and explicitly states it works without requiring an open connection first. This covers the essential 'what it does' and 'how it behaves' for a discovery tool.

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?

Three concise sentences with zero waste: first states purpose, second specifies return values, third provides important usage context. Every sentence earns its place and information is front-loaded appropriately.

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?

For a simple enumeration tool with 0 parameters, no annotations, but an output schema (which handles return value documentation), the description is complete. It covers purpose, return data, and important behavioral context about not needing prior connection, which is exactly what an agent needs to understand when and how to use this discovery 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 tool has 0 parameters with 100% schema description coverage. The description appropriately doesn't discuss parameters since none exist, and instead focuses on what the tool does and returns. This meets the baseline expectation for a parameterless tool.

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 ('列舉所有透過 USB 連線的 J-Link 除錯探針' - enumerate all USB-connected J-Link debug probes) and distinguishes it from siblings by focusing on enumeration rather than connection, control, or RTT operations. It explicitly mentions the resource (J-Link debug probes) and scope (USB-connected).

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 ('此工具不需要先開啟連線即可使用' - this tool can be used without first opening a connection), which implicitly suggests it's for initial discovery before using connection/control tools. However, it doesn't explicitly name alternatives or state when not to use it.

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