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Glama

serial_exchange

Execute a command on an embedded board via serial: temporarily lease it, send the request, wait for the expected prompt or silence, strip the echo, and restore the previous lease state.

Instructions

Atomic composite command execution:

  1. Acquires lease temporarily if not already held.

  2. Transmits command with newline.

  3. Waits for expected prompt or output silence.

  4. Automatically strips echo.

  5. Cleanly restores previous lease state.

Args: board_id: The identifier of the board (e.g. 'board_a') request: Command to execute (e.g. 'help' or 'status') timeout_ms: Maximum duration in milliseconds to wait for reply (default: 1000) expected_prompt: Optional prompt to wait for (e.g. '> ' or 'shell#')

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
requestYes
board_idYes
timeout_msNo
expected_promptNo

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
resultYes

Schema Changelog

Changes observed during successful MCP inspections. Dates show when Glama detected each change.

  1. First observedv0.1.0

TDQS

A4.5/5.0
Behavior4/5

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

With no annotations, the description carries the full burden, and it does well by disclosing transient lease acquisition, automatic echo stripping, waiting for prompt or silence, and restoration of the prior lease state. The main gap is that it does not describe failure behavior on timeout or when lease acquisition fails.

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

Conciseness5/5

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

The description is tightly structured: a one-line purpose, a five-step numbered list, and concise parameter explanations. Every sentence adds information, and the key concept—atomic composite execution—is front-loaded.

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

Completeness4/5

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

Given the tool's complexity, no annotations, and an output schema that exists, the description is largely complete: it explains the operational flow, lease behavior, echo stripping, and all parameters. It only lacks explicit guidance on when to prefer this over related serial tools and what happens on failure, which keeps it just shy of fully complete.

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

Parameters5/5

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

Schema description coverage is 0%, but the description compensates thoroughly by explaining every parameter with concrete examples: board_id ('board_a'), request ('help' or 'status'), timeout_ms (default: 1000), and expected_prompt ('> ' or 'shell#'). This adds meaning well beyond the raw schema property names.

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?

The description opens with 'Atomic composite command execution' and enumerates five concrete steps—lease acquisition, transmission with newline, waiting for prompt/silence, echo stripping, and lease restoration. This clearly identifies the tool as a serial command/response exchange and distinguishes it from siblings like serial_read, serial_write, serial_acquire, and serial_release, which handle only pieces of this flow.

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

Usage Guidelines4/5

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

The steps imply a clear use case: one-shot command execution that needs lease management and synchronous reply handling. It also signals that previous lease state is restored, so it can be used without a prior serial_acquire. However, it does not explicitly name alternatives such as serial_write for fire-and-forget writes or serial_read for passive reading, so some inference is required.

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