Errand Runs MCP Server

plan_run

Plan a single low-energy errand trip covering up to a set number of stores, choosing stops that clear as much of your open list as possible.

Instructions

Plan one low-energy errand run: a single trip covering at most max_stops stores (default 2 - the one-plus-one mode: one main stop, plus one if it clearly helps). The stop combo is picked to chip away as much of the open list as possible, so whatever is left over stays short.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "plan_run"
  }
}

Input Schema

Name	Required	Description	Default
`max_stops`	No

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Nov 14, 2026

TDQS

A3.6/5.0

Behavior3/5

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

With no annotations at all, the description carries the full burden. It usefully discloses the selection heuristic (maximize coverage of the open list, leave a short remainder) and the single-trip constraint, but never says whether planning has side effects, whether it consumes or reserves items, or what happens to the unplanned remainder — all important for an agent deciding to call a planner versus a mutator.

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?

The purpose and the stop cap are front-loaded, and the trailing clause about the leftover list is short and conveys intent rather than restating mechanics. The em-dash parenthetical is slightly wordy but earns its place by explaining the default.

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?

For a one-parameter tool with an output schema, the description covers purpose, the cap semantics, the default, and the optimization goal. The remaining gap is behavioral (side effects, empty-list edge case), which matters more here because no annotations exist to cover it.

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%, so the description must compensate, and it does: it explains that max_stops caps store count, gives the default value of 2, and introduces the 'one-plus-one mode' rationale (one main stop plus one if it clearly helps). That is genuine meaning beyond the bare 'Max Stops' title, though it doesn't state valid ranges or what happens for larger values.

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

Purpose4/5

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

States a specific verb and resource ('Plan one low-energy errand run') and pins the scope: a single trip covering at most max_stops stores. An agent can tell this is a trip-planning tool rather than a list mutation tool like mark_bought or log_item. It stops short of explicitly naming a sibling alternative, but the purpose itself is unambiguous.

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?

Usage is implied rather than stated: 'one low-energy errand run' and 'chip away as much of the open list as possible' suggest calling it when there is an open backlog to consolidate. There is no explicit when-not guidance, no prerequisites, and no statement of what to do if the open list is empty or nothing useful can be planned.

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

Deploy Server