ibmi-mcp

send_key

Send a function or attention key to an IBM i 5250 terminal and receive the updated screen after the host processes the key.

Instructions

Send an attention/function key and wait for the host response.

Args: key: Key name. Valid values: Enter, F1-F24, PageUp, PageDown, Tab, Backtab, Clear, Help, Print, Attn.

Returns the updated screen after the host processes the key.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "key": "<key>"
    },
    "name": "send_key"
  }
}

Input Schema

Name	Required	Description	Default
`key`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0May 17, 2026

TDQS

A3.8/5.0

Behavior3/5

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

No annotations provided, so description carries full burden. It mentions waiting for host response and returning updated screen, but does not disclose destructiveness, idempotency, or error behavior for invalid keys.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences with clear structure; front-loaded with action. The 'Args:' section is slightly verbose but still efficient. No wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given low complexity (single param, no output schema) and no annotations, description covers basic behavior and return value. However, it lacks details on handling invalid keys or timeouts, which would improve completeness.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0% with a single string parameter 'key'. The description adds valuable semantics by listing all valid values (Enter, F1-F24, etc.) and clarifying it is a key name, compensating for the lack of schema description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states the action ('send an attention/function key') and expected outcome ('wait for the host response'), distinguishing it from sibling tools like send_keys (plural) and read_screen.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Valid key values are listed, but no explicit guidance on when to use send_key vs. send_keys (plural) or other alternatives. The description implies usage for single key sends but lacks comparative context.

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

Deploy Server