mcp_call_tool

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

With no annotations, the description carries the full behavioral burden, and it falls short: it does not say what happens on failure, whether arguments are validated against the target tool's schema, what the response looks like, or any permission/timeout concerns. The only behavioral hint is the dynamic-availability condition.

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 short sentences, front-loaded with the action, followed by the usage condition and then the required input format. No waste.

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 dispatcher with no output schema and no annotations, the definition covers the essential action and input format but omits error behavior and any indication of the return shape, which would matter for an agent deciding how to handle the result.

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?

Schema description coverage is 100%, so both parameters are already fully documented ('name' as server-slug__tool-name, 'arguments' as a JSON object). The description restates the namespaced format but adds no syntax or usage detail beyond what the schema provides, so the baseline 3 applies.

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?

States a specific verb and resource ('Call a tool on a connected MCP server'), so an agent immediately knows this dispatches a call to a dynamically connected server. It does not, however, explicitly distinguish itself from siblings like mcp_discover or mcp_connect, leaving the routing between meta-tools to inference.

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?

Provides a clear when-to-use condition: 'when dynamically connected tools aren't directly available.' That is genuine routing guidance, but it names no alternatives (mcp_discover/connect/list_active) and gives no when-not guidance.

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