Mailrith Email Marketing

Schedule or reschedule a broadcast

broadcasts_schedule

DestructiveIdempotent

Schedules a draft for future delivery, or changes the delivery time of an existing scheduled Broadcast. This uses Mailrith's durable scheduled-send path and does not start delivery immediately. Effect: external-email. Retry after reading the current resource state. Permissions: live_actions:write, broadcasts:write. API reference: https://mailrith.com/developers/api-reference.

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": {
      "broadcast_id": "<broadcast_id>",
      "body": "<body>"
    },
    "name": "broadcasts_schedule"
  }
}

Input Schema

Name	Required	Description	Default
`body`	Yes	The exact JSON request body defined by the Mailrith public API contract.
`broadcast_id`	Yes	The broadcast identifier.

Output Schema

Name	Required	Description
`error`	No
`response`	No
`request_id`	Yes	The stable correlation ID for this MCP tool invocation.
`operation_id`	Yes	The stable Mailrith public API operation ID.

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedNov 2, 2026

changedOutput schema / $defs / Broadcast / properties / reply_to_email / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "description": "An override for this email's Reply-To. Null uses the sender's current Reply-To when the email is sent.",
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

Changed5 schema fields changedSep 3, 2026

removedInput schema / $defs / BroadcastScheduleRequest / properties / scheduled_at / format
```
Removed value: -"date-time"
```

addedInput schema / $defs / BroadcastScheduleRequest / properties / scheduled_at / pattern

Added value: +"^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|[+-](?:[01]\\d|2[0-3]):[0-5]\\d)$"

changedOutput schema / $defs / BroadcastEmailDocument / description

Previous value: -"A structured email document. The root node must use type `doc` and contain supported block nodes."New value: +"A structured email document. The root node must use type `doc` and contain supported block nodes. For Subscriber personalization in email subjects and body text nodes, use Mailrith bracket tokens such as [Subscriber_Name, fallback=\"friend\"] or [Subscriber_Email, fallback=\"\"]. Before using a custom field, call custom_fields_list or custom_fields_get and copy its personalization_token exactly. Do not use Handlebars-style variables such as {{ subscriber.name }}; Mailrith sends them as literal text."

changedOutput schema / $defs / BroadcastEmailDocument / example / content

Previous value: -[
-  {
-    "content": [
-      {
-        "text": "Hello from Mailrith.",
-        "type": "text"
-      }
-    ],
-    "type": "paragraph"
-  }
-]New value: +[
+  {
+    "content": [
+      {
+        "text": "Hello [Subscriber_Name, fallback=\"friend\"].",
+        "type": "text"
+      }
+    ],
+    "type": "paragraph"
+  }
+]

changedOutput schema / $defs / BroadcastEmailDocument / examples

Previous value: -[
-  {
-    "content": [
-      {
-        "content": [
-          {
-            "text": "Hello from Mailrith.",
-            "type": "text"
-          }
-        ],
-        "type": "paragraph"
-      }
-    ],
-    "type": "doc"
-  }
-]New value: +[
+  {
+    "content": [
+      {
+        "content": [
+          {
+            "text": "Hello [Subscriber_Name, fallback=\"friend\"].",
+            "type": "text"
+          }
+        ],
+        "type": "paragraph"
+      }
+    ],
+    "type": "doc"
+  }
+]

Changed5 schema fields changedSep 3, 2026

addedInput schema / $defs / BroadcastScheduleRequest / properties / scheduled_at / format
```
Added value: +"date-time"
```

removedInput schema / $defs / BroadcastScheduleRequest / properties / scheduled_at / pattern

Removed value: -"^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|[+-](?:[01]\\d|2[0-3]):[0-5]\\d)$"

changedOutput schema / $defs / BroadcastEmailDocument / description

Previous value: -"A structured email document. The root node must use type `doc` and contain supported block nodes. For Subscriber personalization in email subjects and body text nodes, use Mailrith bracket tokens such as [Subscriber_Name, fallback=\"friend\"] or [Subscriber_Email, fallback=\"\"]. Before using a custom field, call custom_fields_list or custom_fields_get and copy its personalization_token exactly. Do not use Handlebars-style variables such as {{ subscriber.name }}; Mailrith sends them as literal text."New value: +"A structured email document. The root node must use type `doc` and contain supported block nodes."

changedOutput schema / $defs / BroadcastEmailDocument / example / content

Previous value: -[
-  {
-    "content": [
-      {
-        "text": "Hello [Subscriber_Name, fallback=\"friend\"].",
-        "type": "text"
-      }
-    ],
-    "type": "paragraph"
-  }
-]New value: +[
+  {
+    "content": [
+      {
+        "text": "Hello from Mailrith.",
+        "type": "text"
+      }
+    ],
+    "type": "paragraph"
+  }
+]

changedOutput schema / $defs / BroadcastEmailDocument / examples

Previous value: -[
-  {
-    "content": [
-      {
-        "content": [
-          {
-            "text": "Hello [Subscriber_Name, fallback=\"friend\"].",
-            "type": "text"
-          }
-        ],
-        "type": "paragraph"
-      }
-    ],
-    "type": "doc"
-  }
-]New value: +[
+  {
+    "content": [
+      {
+        "content": [
+          {
+            "text": "Hello from Mailrith.",
+            "type": "text"
+          }
+        ],
+        "type": "paragraph"
+      }
+    ],
+    "type": "doc"
+  }
+]

Changed5 schema fields changedAug 17, 2026

removedInput schema / $defs / BroadcastScheduleRequest / properties / scheduled_at / format
```
Removed value: -"date-time"
```

addedInput schema / $defs / BroadcastScheduleRequest / properties / scheduled_at / pattern

Added value: +"^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z|[+-](?:[01]\\d|2[0-3]):[0-5]\\d)$"

changedOutput schema / $defs / BroadcastEmailDocument / description

Previous value: -"A structured email document. The root node must use type `doc` and contain supported block nodes."New value: +"A structured email document. The root node must use type `doc` and contain supported block nodes. For Subscriber personalization in email subjects and body text nodes, use Mailrith bracket tokens such as [Subscriber_Name, fallback=\"friend\"] or [Subscriber_Email, fallback=\"\"]. Before using a custom field, call custom_fields_list or custom_fields_get and copy its personalization_token exactly. Do not use Handlebars-style variables such as {{ subscriber.name }}; Mailrith sends them as literal text."

changedOutput schema / $defs / BroadcastEmailDocument / example / content

Previous value: -[
-  {
-    "content": [
-      {
-        "text": "Hello from Mailrith.",
-        "type": "text"
-      }
-    ],
-    "type": "paragraph"
-  }
-]New value: +[
+  {
+    "content": [
+      {
+        "text": "Hello [Subscriber_Name, fallback=\"friend\"].",
+        "type": "text"
+      }
+    ],
+    "type": "paragraph"
+  }
+]

changedOutput schema / $defs / BroadcastEmailDocument / examples

Previous value: -[
-  {
-    "content": [
-      {
-        "content": [
-          {
-            "text": "Hello from Mailrith.",
-            "type": "text"
-          }
-        ],
-        "type": "paragraph"
-      }
-    ],
-    "type": "doc"
-  }
-]New value: +[
+  {
+    "content": [
+      {
+        "content": [
+          {
+            "text": "Hello [Subscriber_Name, fallback=\"friend\"].",
+            "type": "text"
+          }
+        ],
+        "type": "paragraph"
+      }
+    ],
+    "type": "doc"
+  }
+]

First observedJul 30, 2026

TDQS

A4.1/5.0

Behavior4/5

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

Adds real context beyond the annotations: it names the durable scheduled-send path, declares the external-email effect, lists required permissions (live_actions:write, broadcasts:write), and gives retry guidance. It does not spell out what a reschedule overwrites on an already-scheduled broadcast, which is the main gap given destructiveHint=true.

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?

Front-loaded with the core action and the key negative constraint, then supporting metadata. The permissions line and API reference URL are boilerplate but compact; nothing is redundant with the title.

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?

With an output schema present, return values need no explanation, and annotations carry safety hints. The description supplies effect, permissions, and retry behavior, leaving only the specifics of what rescheduling overwrites unaddressed. Adequate for a two-parameter mutation.

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 description coverage is 100%, so the schema already documents broadcast_id and the scheduled_at future-timestamp with UTC-offset requirement. The description adds no parameter-level detail beyond that, so the 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: schedules a draft for future delivery or changes the delivery time of an existing scheduled Broadcast. The clause 'does not start delivery immediately' cleanly separates it from the immediate-send sibling, and 'changes the delivery time' distinguishes it from broadcasts_unschedule.

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?

Gives clear usage context: use it for drafting a future send or moving an already-scheduled delivery. The 'does not start delivery immediately' note implicitly routes immediate sends to broadcasts_send, and 'Retry after reading the current resource state' gives a recovery pattern. No sibling is named explicitly, so it falls short of a 5.

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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Schedule or reschedule a broadcast

Tool call template

Input Schema

Output Schema

Schema Changelog

TDQS

Glama MCP Gateway

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