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get_message_delivery_receipt

Read-only

Return a message's persisted_at and recipients with kind, read_at, acknowledged, acknowledged_at and admission. Admission observations are historical; null admission means no snapshot was recorded.

Instructions

Return a message's persisted_at and recipients with kind, read_at, acknowledged, acknowledged_at and admission. Admission observations are historical; null admission means no snapshot was recorded. Storage/read/acknowledgement do not establish task acceptance. Null timestamps mean that recipient has not read or acknowledged it yet; they are not delivery errors. Use it as the sender to check an ack_required message; recipients use fetch_inbox. message_id must exist in this project or the call fails with NOT_FOUND.

Input Schema

Name	Required	Description	Default
`message_id`	Yes	Message id.
`project_key`	Yes	Absolute path of the repository's primary checkout.

Output Schema

Name	Required	Description	Default
`revision`	Yes
`message_id`	Yes
`project_id`	Yes
`recipients`	Yes
`persisted_at`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv0.3.1Oct 13, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "additionalProperties": false,
+  "properties": {
+    "message_id": {
+      "type": "integer"
+    },
+    "persisted_at": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "project_id": {
+      "type": "integer"
+    },
+    "recipients": {
+      "items": {
+        "additionalProperties": false,
+        "properties": {
+          "acknowledged": {
+            "type": "boolean"
+          },
+          "acknowledged_at": {
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "admission": {
+            "additionalProperties": false,
+            "properties": {
+              "availability": {
+                "enum": [
+                  "eligible",
+                  "unavailable",
+                  "unknown"
+                ]
+              },
+              "historical": {
+                "type": "boolean"
+              },
+              "lifecycle": {
+                "type": "string"
+              },
+              "observed_at": {
+                "type": "string"
+              },
+              "process": {
+                "enum": [
+                  "present",
+                  "unknown"
+                ]
+              },
+              "reason": {
+                "type": "string"
+              },
+              "recipient": {
+                "type": "string"
+              },
+              "reported_end_at": {
+                "type": "string"
+              },
+              "source": {
+                "enum": [
+                  "t3",
+                  "registry",
+                  "registration"
+                ]
+              },
+              "wake": {
+                "const": "unknown"
+              }
+            },
+            "required": [
+              "recipient",
+              "availability",
+              "lifecycle",
+              "process",
+              "wake",
+              "source",
+              "reason",
+              "observed_at"
+            ],
+            "type": [
+              "object",
+              "null"
+            ]
+          },
+          "kind": {
+            "enum": [
+              "to",
+              "cc",
+              "bcc"
+            ]
+          },
+          "read_at": {
+            "type": [
+              "string",
+              "null"
+            ]
+          },
+          "recipient": {
+            "type": "string"
+          },
+          "withdrawn_at": {
+            "type": [
+              "string",
+              "null"
+            ]
+          }
+        },
+        "required": [
+          "recipient",
+          "kind",
+          "read_at",
+          "acknowledged",
+          "acknowledged_at",
+          "withdrawn_at",
+          "admission"
+        ],
+        "type": "object"
+      },
+      "type": "array"
+    },
+    "revision": {
+      "type": "integer"
+    }
+  },
+  "required": [
+    "message_id",
+    "project_id",
+    "persisted_at",
+    "revision",
+    "recipients"
+  ],
+  "type": "object"
+}

First observedv0.2.1Oct 4, 2026

TDQS

A4.8/5.0

Behavior5/5

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

Annotations only declare readOnlyHint/openWorldHint, but the description adds substantial behavioral context: admission observations are historical and null means no snapshot, null timestamps are not errors, and storage/read/ack do not imply task acceptance. It also discloses the NOT_FOUND failure mode, which annotations cannot express.

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-loads the return payload, then adds the semantic caveats and the role-based routing. Dense but every sentence carries distinct information; only minor tightening is possible.

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?

Given an output schema exists, the description need not document returns, yet it still covers role applicability, null-value semantics, non-equivalence of ack and acceptance, and the failure condition — everything an agent needs to interpret results correctly.

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 100%, so baseline is 3; the description goes beyond the schema by stating message_id 'must exist in this project or the call fails with NOT_FOUND,' adding an error constraint not captured in the property docs.

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 (Return) and resource (a message's delivery receipt), and enumerates the fields returned (persisted_at, recipients, read_at, acknowledged, admission). It also distinguishes itself from the sibling fetch_inbox by naming which role uses which tool.

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?

Explicitly routes by role: 'Use it as the sender to check an ack_required message; recipients use fetch_inbox.' Names both the condition for use and the alternative tool, leaving nothing to inference.

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