probe_connect

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

Annotations already declare readOnlyHint=false, so the agent knows this is not read-only. The description adds that it returns connectionId and server info, which is helpful. However, it does not disclose that the connection remains open and requires a subsequent probe_disconnect call, which is a significant behavioral detail beyond what annotations provide.

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, well-structured sentence that front-loads the main action and return information. Every word earns its place; there is no redundancy or filler.

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 has 5 parameters and no output schema, the description does well by stating what it returns (connectionId, name, version, capabilities, counts). It misses the caveat that the connection persists and should be closed via probe_disconnect, which would make it more complete for an agent managing resources.

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 covers 100% of the parameters, providing descriptions for transport, command, url, args, and env. The description adds no parameter-level detail beyond what the schema already gives, so it meets the baseline for high schema coverage without needing compensation.

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 uses a specific verb ('Open a connection'), names the resource ('MCP target server'), and specifies the transports (stdio or HTTP). It also states the return value (connectionId and server info), which clearly distinguishes it from siblings like probe_disconnect and probe_list.

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 clearly implies when this tool is used—when you need to establish a connection to an MCP server. It doesn't explicitly mention alternatives or exclusions, but the sibling names and the action of 'probe_connect' make the context obvious, so it earns a 4 for clear context without explicit guidance.

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