MartinLoop — Stop Runaway Loops, Bad Code & Token Waste

martin_cancel

Destructive

Record a durable cancellation receipt for one MartinLoop run using file, loopId, or latest, with optional reason and requester. Use to abandon work permanently; it does not kill processes.

Instructions

Write a durable cancellation receipt for one canonical MartinLoop run. Provide exactly one selector: file, loopId, or latest; runsDir changes the run-store root, while reason and requestedBy add audit context. Use when work must be abandoned, not temporarily held. This records a request and does not kill a process; use martin_pause for a reversible hold.

Input Schema

Name	Required	Description
`file`	No	Path to one canonical run record or directory. Mutually exclusive with loopId and latest.
`latest`	No	When true, targets the latest canonical run. Mutually exclusive with file and loopId.
`loopId`	No	Canonical MartinLoop run identifier. Mutually exclusive with file and latest.
`reason`	No	Optional non-empty reason recorded in the cancellation receipt.
`runsDir`	No	Optional run-store root override used to resolve loopId or latest.
`requestedBy`	No	Optional human or runtime identity label recorded for audit context.

Output Schema

Name	Required	Description
`ok`	Yes	Whether the control receipt was recorded.
`state`	Yes	Run control state after this request, including all recorded receipts.
`action`	Yes	The control action that was recorded.
`loopId`	Yes	MartinLoop run identifier the control was applied to.
`reason`	No	Human-readable reason for the control, if provided.
`summary`	Yes	Human-readable result of the control request.
`controlId`	Yes	Unique receipt ID for this control action.
`requestedAt`	Yes	ISO 8601 timestamp when the control was recorded.
`requestedBy`	No	Identity that requested the control, if provided.
`requestedAction`	Yes	The control action that was requested.

Schema Changelog

Changes observed during successful MCP inspections.

Changed5 schema fields changedv0.8.6Oct 16, 2026

addedOutput schema / properties / ok

Added value: +{
+  "description": "Whether the control receipt was recorded.",
+  "type": "boolean"
+}

addedOutput schema / properties / requestedAction

Added value: +{
+  "description": "The control action that was requested.",
+  "enum": [
+    "pause",
+    "cancel",
+    "continue"
+  ],
+  "type": "string"
+}

addedOutput schema / properties / state

Added value: +{
+  "additionalProperties": true,
+  "description": "Run control state after this request, including all recorded receipts.",
+  "type": "object"
+}

addedOutput schema / properties / summary

Added value: +{
+  "description": "Human-readable result of the control request.",
+  "type": "string"
+}

changedOutput schema / required

Previous value: -[
-  "loopId",
-  "action",
-  "controlId",
-  "requestedAt"
-]New value: +[
+  "loopId",
+  "action",
+  "controlId",
+  "requestedAt",
+  "ok",
+  "summary",
+  "requestedAction",
+  "state"
+]

Changed1 schema field changedv0.6.6Sep 23, 2026

removedInput schema / oneOf

Removed value: -[
-  {
-    "required": [
-      "file"
-    ]
-  },
-  {
-    "required": [
-      "loopId"
-    ]
-  },
-  {
-    "required": [
-      "latest"
-    ]
-  }
-]

Changed6 schema fields changedv0.5.9Sep 2, 2026

addedInput schema / properties / file / description

Added value: +"Path to one canonical run record or directory. Mutually exclusive with loopId and latest."

addedInput schema / properties / latest / description

Added value: +"When true, targets the latest canonical run. Mutually exclusive with file and loopId."

addedInput schema / properties / loopId / description

Added value: +"Canonical MartinLoop run identifier. Mutually exclusive with file and latest."

addedInput schema / properties / reason / description

Added value: +"Optional non-empty reason recorded in the cancellation receipt."

addedInput schema / properties / requestedBy / description

Added value: +"Optional human or runtime identity label recorded for audit context."

addedInput schema / properties / runsDir / description

Added value: +"Optional run-store root override used to resolve loopId or latest."

Changed3 schema fields changedv0.5.6Aug 30, 2026

changedOutput schema / additionalProperties
```
Previous value: -trueNew value: +false
```

addedOutput schema / properties

Added value: +{
+  "action": {
+    "description": "The control action that was recorded.",
+    "enum": [
+      "pause",
+      "cancel",
+      "continue"
+    ],
+    "type": "string"
+  },
+  "controlId": {
+    "description": "Unique receipt ID for this control action.",
+    "type": "string"
+  },
+  "loopId": {
+    "description": "MartinLoop run identifier the control was applied to.",
+    "type": "string"
+  },
+  "reason": {
+    "description": "Human-readable reason for the control, if provided.",
+    "type": "string"
+  },
+  "requestedAt": {
+    "description": "ISO 8601 timestamp when the control was recorded.",
+    "type": "string"
+  },
+  "requestedBy": {
+    "description": "Identity that requested the control, if provided.",
+    "type": "string"
+  }
+}

addedOutput schema / required

Added value: +[
+  "loopId",
+  "action",
+  "controlId",
+  "requestedAt"
+]

First observedv0.3.9Jul 29, 2026

TDQS

A4.7/5.0

Behavior4/5

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

The destructiveHint=true annotation could mislead an agent into thinking a process is killed; the description corrects this directly ('This records a request and does not kill a process') and adds audit-context intent. It doesn't address the idempotentHint=false implication of repeat calls, which is a minor remaining gap.

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?

Three sentences, front-loaded with the action and selector constraint, then usage guidance, then the critical behavioral caveat. No redundant restatement of the name or schema.

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

Completeness5/5

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

With an output schema present, return values need not be explained, and the description still covers the selector contract, store-root override, audit fields, and the distinction from martin_pause. Nothing an agent needs to call this correctly is missing.

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 already 100%, so the baseline is 3. The description adds framing beyond the schema by stating the 'exactly one selector' grouping and clarifying roles (runsDir changes the run-store root; reason/requestedBy supply audit context), which helps an agent assemble a valid call.

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?

States a specific verb and resource: 'Write a durable cancellation receipt for one canonical MartinLoop run.' It also distinguishes itself from the sibling martin_pause by name, so an agent can differentiate without opening either schema.

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

Usage Guidelines5/5

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

Gives an explicit trigger ('Use when work must be abandoned, not temporarily held') plus the alternative and its selection condition ('use martin_pause for a reversible hold'). Both when-to-use and when-not-to-use are covered.

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