call_installed_mcp_tool

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

Goes meaningfully beyond the annotations: it warns that results are untrusted data rather than instructions (a real prompt-injection caveat), and that each call cold-starts the server so latency of several seconds is expected. It also discloses the operator-enablement gate. What it omits is that the invoked tool may itself be mutating despite destructiveHint=false on this wrapper, which an agent could misread.

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 tight sentences, each earning its place: capability, permission boundary, then trust and latency caveats. Front-loaded with the core action and no redundant restatement of the tool name.

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?

An output schema exists so return values need no explanation, and the description covers the remaining agent-relevant concerns — discovery path, permission gating, latency, and data trust. Nothing needed to invoke this dispatcher correctly is missing.

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 coverage is 100%, so the schema already documents all four parameters, including that 'arguments' must match the target tool's input schema. The description repeats little of that and adds no syntax or shape guidance beyond what the schema states, so 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 one tool of a local MCP server the operator installed for this project') and names the sibling it pairs with (list_installed_mcp_tools). An agent can immediately distinguish this dispatcher from discovery or project-level tools in the sibling 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?

Gives a concrete precondition — only server+tool pairs enabled via the local CLI are accepted — and routes discovery to list_installed_mcp_tools. It lacks an explicit 'do not use when' clause or a mention of when a direct/sibling tool would be preferable, which keeps it short of a 5.

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