Tool use id bug

[leoisadev1]

Description

I uploaded 2 images and a short message, got hit with this error.

OpenCode version

1.0.167

Steps to reproduce

1. Upload 2 images with ctrl + v
2. Add a short message
3. Click enter

Screenshot and/or share link

Operating System

macOS 26.2

Terminal

Ghostty

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• AI_APICallError: tool_use blocks found without corresponding tool_result blocks #2720: AI_APICallError: tool_use blocks found without corresponding tool_result blocks
• AI_APICallError: tool_use ids were found without tool_result blocks immediately after #1662: AI_APICallError: tool_use ids were found without tool_result blocks immediately after
• AI_APICallError: messages.1.content.2: tool_use ids must be unique #1279: AI_APICallError: messages.1.content.2: tool_use ids must be unique
• AI_APICallError: tool_use ids must be unique #1150: AI_APICallError: tool_use ids must be unique
• In Memory Image can't be Pasted in Opencode After TUI Upgrade. #4077: In Memory Image can't be Pasted in Opencode After TUI Upgrade (image-related issues)
• Switching from an image supported model to a non-image model breaks the thread #5101: Switching from an image supported model to a non-image model breaks the thread (image handling)

Feel free to ignore if none of these address your specific case.

[rekram1-node]

ill look into it

[rekram1-node]

How do I replicate?

I saw ur description but I think this prolly has to do w/ ordering and whatnot

If u could export session: opencode export > session.json it'd be amazing

[deriegle]

https://gist.github.com/deriegle/db117ea51f6f55e814e855541bcd47ee

I ran into this too. I had a longer session and was on the main branch in my repo. I had a few files staged and ran /rmslop (same as in opencode) and ran into this bug. I opened a new session and ran /rmslop and got the error again. The gist above is from the second session.

EDIT: realizing the way mine happened was different (no images uploaded) but the error was similar in case that's helpful. Otherwise we can mark this as unrelated.

[rekram1-node]

@deriegle can u give me the raw json export tho? opencode export > session.json

[deriegle]

Sorry about that. I've added the session.json into this gist: https://gist.github.com/deriegle/db117ea51f6f55e814e855541bcd47ee

Several of the calls outputted my entire files since it was diffing them, I obfuscated the file names & outputs. If those end up being required to debug this, I can find another way to share that.

[Mishkun]

https://gist.github.com/Mishkun/02648359700010e559f7edf6bc8ac4dd

@rekram1-node I finally got this on a pet project, so I can share one in the full

[westito]

I get this error many times so logged out and tried investigate with Opus. What I found.
(I posted this on other issue, but marked as off-topic - this issue is more related)

Tool Validation Error: Missing tool_result After Interruption

Root Cause

Client doesn't insert tool_result message after interruption before allowing model to continue.

When abort happens, client appends retry to the SAME assistant message instead of starting a new turn with tool_result in between.

Summary

Anthropic's Messages API rejects conversation history when an assistant message contains content (thinking/text) AFTER a tool_use block. The API expects tool_result immediately after tool_use, but when content appears in between, validation fails.

Error Message

messages.{N}: `tool_use` ids were found without `tool_result` blocks immediately after: {tool_id}. 
Each `tool_use` block must have a corresponding `tool_result` block in the next message.

The Rule

All tool_use blocks must be contiguous at the END of the assistant message content.

Once a tool_use block appears, only more tool_use blocks can follow. Any other content (thinking, text) AFTER a tool_use is invalid.

Valid vs Invalid Patterns

Valid: Tools grouped at end

assistant: [thinking, text, tool_use_A, tool_use_B]
user: [tool_result_A, tool_result_B]

Valid: Separate turns per tool

assistant: [thinking, text, tool_use_A]
user: [tool_result_A]
assistant: [thinking, text, tool_use_B]
user: [tool_result_B]

Invalid: Content AFTER tool_use

assistant: [thinking, tool_use_A, thinking, tool_use_B]  ← thinking AFTER tool_A!
user: [tool_result_A, tool_result_B]

Error: tool_use ids were found without tool_result blocks immediately after: tool_A

The API sees content after tool_use_A and interprets it as: "tool_A should have gotten its result before the assistant generated more content."

How This Happens

When a user aborts a tool mid-stream:

What should happen:

assistant: [thinking, tool_A]       ← END turn here
user: [tool_result_A: "aborted"]    ← INSERT this
assistant: [thinking, tool_B]       ← NEW turn
user: [tool_result_B]

What actually happens:

assistant: [thinking, tool_A, thinking, tool_B]  ← appended to SAME message
user: [tool_result_A, tool_result_B]             ← both results bundled

The sequence:

1. Model generates: thinking → tool_A
2. User aborts during tool execution
3. Client saves: thinking → tool_A (aborted)
4. BUG: Client does NOT end turn and add tool_result
5. Model retries, client appends: thinking → tool_B
6. Result: [thinking, tool_A, thinking, tool_B] - invalid pattern

Other causes:

• Network interruption during streaming
• Timeout kills the stream
• Client crash during streaming
• Rate limiting mid-response

Real-World Example

Saved message parts

prt_..5001 → step-start
prt_..7001 → reasoning: "The user wants me to create a markdown file..."
prt_..6001 → tool: write (ERROR, input: {})  ← ABORTED
prt_..b001 → reasoning: "The user wants me to create a markdown file..."
prt_..7001 → tool: write (COMPLETED)
prt_..c001 → step-finish

Converted to API format:

{
  "role": "assistant",
  "content": [
    {"type": "thinking", "thinking": "..."},
    {"type": "tool_use", "id": "toolu_01LiPBp", "name": "write", "input": {}},
    {"type": "thinking", "thinking": "..."},
    {"type": "tool_use", "id": "toolu_016rCwe", "name": "write", "input": {...}}
  ]
}

API Error:

messages.49: `tool_use` ids were found without `tool_result` blocks immediately after: toolu_01LiPBp

Workaround

Before sending to API, restructure messages with interleaved content:

Option A - Split into separate turns:

Original: assistant[thinking, tool_A, thinking, tool_B] + user[result_A, result_B]

Fixed:
  assistant[thinking, tool_A] + user[result_A]
  assistant[thinking, tool_B] + user[result_B]

Option B - Group tools at end (if results exist):

Original: [thinking, tool_A, thinking, tool_B]

Fixed: [thinking, thinking, tool_A, tool_B]

Note: Only works if the tool results are bundled together in the next message.

Test Results

Pattern	Result
[thinking, text, tool_A, tool_B] → [result_A, result_B]	✅ SUCCESS
[thinking, tool_A, thinking, tool_B] → [result_A, result_B]	❌ FAILED
[thinking, text, tool_A, thinking, text, tool_B] → [result_A, result_B]	❌ FAILED
[thinking, text, tool_A] → [result_A] → [thinking, text, tool_B] → [result_B]	✅ SUCCESS

Minimal Reproduction

curl -X POST https://api.anthropic.com/v1/messages \
  -H "x-api-key: $ANTHROPIC_API_KEY" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: interleaved-thinking-2025-05-14" \
  -H "content-type: application/json" \
  -d '{
    "model": "claude-sonnet-4-20250514",
    "max_tokens": 2048,
    "thinking": {"type": "enabled", "budget_tokens": 1024},
    "messages": [
      {"role": "user", "content": "Do two things"},
      {
        "role": "assistant",
        "content": [
          {"type": "thinking", "thinking": "First.", "signature": "VALID_SIG_HERE"},
          {"type": "tool_use", "id": "tool_1", "name": "do_thing", "input": {"x": 1}},
          {"type": "thinking", "thinking": "Second.", "signature": "VALID_SIG_HERE"},
          {"type": "tool_use", "id": "tool_2", "name": "do_thing", "input": {"x": 2}}
        ]
      },
      {
        "role": "user",
        "content": [
          {"type": "tool_result", "tool_use_id": "tool_1", "content": "done"},
          {"type": "tool_result", "tool_use_id": "tool_2", "content": "done"}
        ]
      }
    ],
    "tools": [{"name": "do_thing", "description": "Do", "input_schema": {"type": "object", "properties": {"x": {"type": "integer"}}}}]
  }'

Expected error:

{
  "type": "error",
  "error": {
    "type": "invalid_request_error",
    "message": "messages.1: `tool_use` ids were found without `tool_result` blocks immediately after: tool_1"
  }
}

[prolific]

I am also getting this error way too many times. Makes the current session completely unusable.