---
title: "Check completion example protocol support"
description: "MCP Description does not support completion examples for MCP 2024-11-05, despite the underlying protocol defining completion. The registry records that deliberate historical limita"
source: "https://mcpdesc.org/docs/rules/0.9.0-rc.3/mcp/completion-protocol-version/"
---

MCP Description does not support completion examples for MCP 2024-11-05, despite the underlying protocol defining completion. The registry records that deliberate historical limitation. Scope completion examples to supported versions instead of treating this as a missing capability advertisement.

## Requirement

Completion examples are available in every protocol version that defines completion/complete and CompleteResult.

## Details

**Rule ID:** `mcp.completion.protocol-version`  
**Owner:** mcp  
**Surface:** CompleteResult  
**Kind:** structural  
**Requirement level:** Not specified in the rule record  
**Status:** internal · **Enforcement:** internal

## Protocol version applicability

| 2024-11-05 | 2025-03-26 | 2025-06-18 | 2025-11-25 | 2026-07-28 |
| ---------- | ---------- | ---------- | ---------- | ---------- |
| applies    | applies    | applies    | applies    | applies    |

## Required by

* **MCP Description 0.9.0, Sections 10.4.6 and 11.4 (no completion examples for MCP 2024-11-05)**  
  * 10\. Resources and Resource Templates: [req-template-completion-protocol-versions](https://mcpdesc.org/docs/specification/0.9.0-rc.3/resources#req-template-completion-protocol-versions)
  * 1. Prompts: [req-prompt-completion-protocol-versions](https://mcpdesc.org/docs/specification/0.9.0-rc.3/prompts#req-prompt-completion-protocol-versions)

## Based on

* **Tier 1 — MCP schema.ts and normative specification text:** MCP 2024-11-05 schema.ts, interfaces CompleteRequest (method completion/complete) and CompleteResult; the ServerCapabilities.completions capability is added in MCP 2025-03-26  
  * [validation/mcp-schemas/2024-11-05/schema.ts#L951-L972](https://github.com/modelcontextprotocol/modelcontextprotocol/blob/dae694f61a31f7a3ec2af3aff709e11f70f61e48/schema/2024-11-05/schema.ts#L951-L972)
  * [validation/mcp-schemas/2024-11-05/schema.ts#L974-L992](https://github.com/modelcontextprotocol/modelcontextprotocol/blob/dae694f61a31f7a3ec2af3aff709e11f70f61e48/schema/2024-11-05/schema.ts#L974-L992)
  * [validation/mcp-schemas/2025-03-26/schema.ts#L237-L240](https://github.com/modelcontextprotocol/modelcontextprotocol/blob/dae694f61a31f7a3ec2af3aff709e11f70f61e48/schema/2025-03-26/schema.ts#L237-L240)

## Gaps and arbitrations

Known gap: `2024-11-05`

Completion examples are rejected with completion-example-version-mismatch, although MCP 2024-11-05 defines completion/complete. MCP Description does not support completion examples for this protocol version: it is old and the use case is narrow.

Resolution: **not-fixed** (Maintainer decision on issue #72, 2026-10-25).

## Examples

### Valid example

Source: [expected-warning/legacy-completion-examples.json](https://github.com/mcpdesc/mcpdesc-specification/blob/v0.9.0-rc.3/spec/draft/fixtures/expected-warning/legacy-completion-examples.json) · Selected: `/resourceTemplates/0/completionExamples/issue-prefix`

```json
{
  "argument": {
    "name": "issue",
    "value": "12"
  },
  "result": {
    "completion": {
      "values": [
        "120",
        "121",
        "129"
      ],
      "hasMore": true,
      "total": 14
    },
    "_meta": {
      "trace": "c1"
    }
  }
}
```

### Invalid example

Source: [expected-invalid/invalid-completion-example-semantics.json](https://github.com/mcpdesc/mcpdesc-specification/blob/v0.9.0-rc.3/spec/draft/fixtures/expected-invalid/invalid-completion-example-semantics.json) · Selected: `/prompts/0/completionExamples`

```json
{
  "unsupported-version": {
    "argument": {
      "name": "topic",
      "value": "ch"
    },
    "result": {
      "completion": {
        "values": [
          "chess"
        ]
      }
    }
  }
}
```

## Rule Source Code

[result.yaml](https://github.com/mcpdesc/mcpdesc-specification/blob/v0.9.0-rc.3/spec/draft/validation/rules/result.yaml) at immutable tag [v0.9.0-rc.3](https://github.com/mcpdesc/mcpdesc-specification/blob/v0.9.0-rc.3/spec/draft).