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Pause a heartbeat monitor

pause_heartbeat

Idempotent

Pause a heartbeat to suppress late reports and close open incidents without alerts when a job is intentionally stopped, like a runner taken out of service.

Instructions

Pause one heartbeat: it is no longer reported late, pings to its ping_url are accepted but ignored, and its open incident closes without an alert. Use it when the job is stopped on purpose, such as a runner taken out of service; resume_heartbeat undoes it, while delete_heartbeat removes the heartbeat for good. Maintenance windows do not cover heartbeats. Requires a key with the write scope. Pausing a paused heartbeat changes nothing. Returns the heartbeat.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`heartbeat_id`	Yes	The heartbeat's uuid from list_heartbeats. An id that is not a heartbeat of this organization, or a deleted one, is a 404.

Output Schema

TableJSON Schema

Name	Required	Description
`id`	Yes
`name`	Yes
`tags`	No
`state`	Yes	Known values: PENDING, UP, DOWN, PAUSED.
`ping_url`	Yes
`is_active`	Yes
`created_at`	Yes
`overdue_at`	Yes
`updated_at`	Yes
`channel_ids`	No
`last_ping_at`	Yes
`grace_seconds`	Yes
`last_start_at`	Yes
`period_seconds`	Yes
`last_success_at`	Yes
`last_duration_ms`	Yes
`notification_cooldown_seconds`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv0.6.1Oct 20, 2026

addedInput schema / properties / heartbeat_id / description

Added value: +"The heartbeat's uuid from list_heartbeats. An id that is not a heartbeat of this organization, or a deleted one, is a 404."

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "properties": {
+    "channel_ids": {
+      "items": {
+        "format": "uuid",
+        "type": "string"
+      },
+      "type": "array"
+    },
+    "created_at": {
+      "type": "string"
+    },
+    "grace_seconds": {
+      "type": "integer"
+    },
+    "id": {
+      "format": "uuid",
+      "type": "string"
+    },
+    "is_active": {
+      "type": "boolean"
+    },
+    "last_duration_ms": {
+      "anyOf": [
+        {
+          "type": "integer"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    },
+    "last_ping_at": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    },
+    "last_start_at": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    },
+    "last_success_at": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    },
+    "name": {
+      "type": "string"
+    },
+    "notification_cooldown_seconds": {
+      "type": "integer"
+    },
+    "overdue_at": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    },
+    "period_seconds": {
+      "type": "integer"
+    },
+    "ping_url": {
+      "type": "string"
+    },
+    "state": {
+      "description": "Known values: PENDING, UP, DOWN, PAUSED.",
+      "type": "string"
+    },
+    "tags": {
+      "items": {
+        "type": "string"
+      },
+      "type": "array"
+    },
+    "updated_at": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "id",
+    "name",
+    "state",
+    "period_seconds",
+    "grace_seconds",
+    "ping_url",
+    "last_ping_at",
+    "last_success_at",
+    "last_start_at",
+    "last_duration_ms",
+    "overdue_at",
+    "notification_cooldown_seconds",
+    "is_active",
+    "created_at",
+    "updated_at"
+  ],
+  "type": "object"
+}

First observedv0.5.4Oct 20, 2026

TDQS

A4.7/5.0

Behavior5/5

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

Goes well beyond the annotations: pings are accepted but ignored, an open incident is closed without an alert, a write-scoped key is required, and pausing an already-paused heartbeat is a no-op. This is exactly the operational context the annotations (idempotentHint, destructiveHint) cannot convey.

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?

Four tightly packed sentences, front-loaded with the effect of pausing, then usage, then alternatives and prerequisites. No filler sentences; even the trailing 'Returns the heartbeat' is one short clause.

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?

Mutation tool with an output schema and full annotation coverage, and the description still covers side effects, auth scope, idempotency, and sibling routing. 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.

Parameters3/5

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

Schema coverage is 100% and the single heartbeat_id parameter is already fully documented in the schema (uuid source, 404 semantics). The description adds no parameter-level detail, so baseline 3 applies.

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 ('Pause one heartbeat') and immediately qualifies scope by naming the sibling alternatives resume_heartbeat and delete_heartbeat. An agent can distinguish this from resume/delete without opening schemas.

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?

Explicit when-to-use condition ('when the job is stopped on purpose, such as a runner taken out of service'), plus explicit when-not/alternatives: resume_heartbeat undoes it, delete_heartbeat removes it permanently, and maintenance windows do not cover heartbeats.

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

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