compaction-threshold changedbuild-with-claude/compaction-threshold
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Lines−194removed
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Recorded edits15to this page, all time
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13931393
13941394You must pass the `compaction` block back to the API on subsequent requests to continue the conversation with the shortened prompt. The simplest approach is to append the entire response content to your messages:
13951395
1396<CodeGroup>
1397 ```bash cURL
1398 # The response content, including the compaction block, must go back to the
1399 # API as the assistant turn of the next request. Managing that message list
1400 # doesn't translate well to a one-off shell command; see the CLI and SDK
1401 # tabs for the full flow. First request:
1402 curl https://api.anthropic.com/v1/messages \
1403 -H "x-api-key: $ANTHROPIC_API_KEY" \
1404 -H "anthropic-version: 2023-06-01" \
1405 -H "anthropic-beta: compact-2026-01-12" \
1406 -H "content-type: application/json" \
1407 -d '{
1408 "model": "claude-opus-5-5",
1409 "max_tokens": 4096,
1410 "messages": [
1411 {
1412 "role": "user",
1413 "content": "Hello, Claude"
1414 }
1415 ],
1416 "context_management": {
1417 "edits": [
1418 {
1419 "type": "compact_20260112"
1420 }
1421 ]
1422 }
1423 }'
1424 ```
1396<CodeGroup exclude="shell:cURL, shell:CLI">
1397 <CodeGroupItem language="cURL">
1398 This workflow needs more logic than a single shell command. Use the [Claude SDK](https://platform.claude.com/docs/en/cli-sdks-libraries/overview) to run it.
1399 </CodeGroupItem>
14251400
1426 ```bash CLI
1427 ant beta:messages create \
1428 --beta compact-2026-01-12 \
1429 --transform content \
1430 --format jsonl <<'YAML' > content.json
1431 model: claude-opus-5-5
1432 max_tokens: 4096
1433 messages:
1434 - role: user
1435 content: Hello, Claude
1436 context_management:
1437 edits:
1438 - type: compact_20260112
1439 YAML
1401 <CodeGroupItem language="CLI">
1402 This workflow needs more logic than a single shell command. Use the [Claude SDK](https://platform.claude.com/docs/en/cli-sdks-libraries/overview) to run it.
1403 </CodeGroupItem>
14401404
1441 # After receiving a response with a compaction block, append it as the
1442 # assistant turn and continue the conversation
1443 ant beta:messages create --beta compact-2026-01-12 <<YAML
1444 model: claude-opus-5-5
1445 max_tokens: 4096
1446 messages:
1447 - role: user
1448 content: Hello, Claude
1449 - role: assistant
1450 content: $(cat content.json)
1451 - role: user
1452 content: Now add error handling
1453 context_management:
1454 edits:
1455 - type: compact_20260112
1456 YAML
1457 ```
1458
14591405 ```python Python
14601406 client = anthropic.Anthropic()
14611407 messages = [{"role": "user", "content": "Hello, Claude"}]
from line 2330
23842330 ```
23852331
23862332 ```bash CLI
2387 CURRENT=$(ant beta:messages count-tokens \
2388 --beta compact-2026-01-12 \
2389 --transform input_tokens \
2390 --raw-output <<'YAML'
2333 ant beta:messages count-tokens \
2334 --beta compact-2026-01-12 <<'YAML'
23912335 model: claude-opus-5-5
23922336 messages:
23932337 - role: user
from line 2340
23962340 edits:
23972341 - type: compact_20260112
23982342 YAML
2399 )
2400
2401 ORIGINAL=$(ant beta:messages count-tokens \
2402 --beta compact-2026-01-12 \
2403 --transform context_management.original_input_tokens \
2404 --raw-output <<'YAML'
2405 model: claude-opus-5-5
2406 messages:
2407 - role: user
2408 content: Hello, Claude
2409 context_management:
2410 edits:
2411 - type: compact_20260112
2412 YAML
2413 )
2414
2415 printf 'Current tokens: %s\n' "$CURRENT"
2416 printf 'Original tokens: %s\n' "$ORIGINAL"
24172343 ```
24182344
24192345 ```python Python
from line 2480
25542480
25552481Here's a complete example of a long-running conversation with compaction:
25562482
2557<CodeGroup>
2558 ```bash cURL
2559 # curl sends individual requests; maintain the messages array in the
2560 # calling script. See the SDK tabs for the full chat() loop. Single-turn
2561 # request shape:
2562 curl https://api.anthropic.com/v1/messages \
2563 -H "x-api-key: $ANTHROPIC_API_KEY" \
2564 -H "anthropic-version: 2023-06-01" \
2565 -H "anthropic-beta: compact-2026-01-12" \
2566 -H "content-type: application/json" \
2567 -d '{
2568 "model": "claude-opus-5-5",
2569 "max_tokens": 4096,
2570 "messages": [
2571 {
2572 "role": "user",
2573 "content": "Help me build a Python web scraper"
2574 }
2575 ],
2576 "context_management": {
2577 "edits": [
2578 {
2579 "type": "compact_20260112",
2580 "trigger": {
2581 "type": "input_tokens",
2582 "value": 100000
2583 }
2584 }
2585 ]
2586 }
2587 }'
2588 ```
2483<CodeGroup exclude="shell:cURL, shell:CLI">
2484 <CodeGroupItem language="cURL">
2485 This workflow needs more logic than a single shell command. Use the [Claude SDK](https://platform.claude.com/docs/en/cli-sdks-libraries/overview) to run it.
2486 </CodeGroupItem>
25892487
2590 ```bash CLI
2591 # The CLI handles individual turns; maintain the messages array in the
2592 # calling script. See the SDK tabs for the full chat() loop. Single-turn
2593 # request shape:
2594 ant beta:messages create \
2595 --beta compact-2026-01-12 \
2596 --transform 'content.#(type=="text").text' \
2597 --raw-output <<'YAML'
2598 model: claude-opus-5-5
2599 max_tokens: 4096
2600 messages:
2601 - role: user
2602 content: Help me build a Python web scraper
2603 context_management:
2604 edits:
2605 - type: compact_20260112
2606 trigger:
2607 type: input_tokens
2608 value: 100000
2609 YAML
2610 ```
2488 <CodeGroupItem language="CLI">
2489 This workflow needs more logic than a single shell command. Use the [Claude SDK](https://platform.claude.com/docs/en/cli-sdks-libraries/overview) to run it.
2490 </CodeGroupItem>
26112491
26122492 ```python Python
26132493 client = anthropic.Anthropic()
from line 2782
29022782
29032783Here's an example that uses `pause_after_compaction` to preserve the prior exchange and the current user message (three messages total) instead of summarizing them. It keeps their text and tool blocks unchanged, removes the `thinking` and `redacted_thinking` blocks from the preserved assistant turn, and drops that turn if nothing else is left:
29042784
2905<CodeGroup>
2906 ```bash cURL
2907 # curl sends individual requests; maintain the messages array in the
2908 # calling script. See the SDK tabs for the full chat() loop with
2909 # pause-and-preserve handling. Single-turn request shape:
2910 curl https://api.anthropic.com/v1/messages \
2911 -H "x-api-key: $ANTHROPIC_API_KEY" \
2912 -H "anthropic-version: 2023-06-01" \
2913 -H "anthropic-beta: compact-2026-01-12" \
2914 -H "content-type: application/json" \
2915 -d '{
2916 "model": "claude-opus-5-5",
2917 "max_tokens": 4096,
2918 "messages": [
2919 {
2920 "role": "user",
2921 "content": "Help me build a Python web scraper"
2922 }
2923 ],
2924 "context_management": {
2925 "edits": [
2926 {
2927 "type": "compact_20260112",
2928 "trigger": {
2929 "type": "input_tokens",
2930 "value": 100000
2931 },
2932 "pause_after_compaction": true
2933 }
2934 ]
2935 }
2936 }'
2937 ```
2785<CodeGroup exclude="shell:cURL, shell:CLI">
2786 <CodeGroupItem language="cURL">
2787 This workflow needs more logic than a single shell command. Use the [Claude SDK](https://platform.claude.com/docs/en/cli-sdks-libraries/overview) to run it.
2788 </CodeGroupItem>
29382789
2939 ```bash CLI
2940 # The CLI handles individual turns; maintain the messages array in the
2941 # calling script. See the SDK tabs for the full chat() loop with
2942 # pause-and-preserve handling. Single-turn request shape:
2943 ant beta:messages create \
2944 --beta compact-2026-01-12 \
2945 --transform 'content.#(type=="text").text' \
2946 --raw-output <<'YAML'
2947 model: claude-opus-5-5
2948 max_tokens: 4096
2949 messages:
2950 - role: user
2951 content: Help me build a Python web scraper
2952 context_management:
2953 edits:
2954 - type: compact_20260112
2955 trigger:
2956 type: input_tokens
2957 value: 100000
2958 pause_after_compaction: true
2959 YAML
2960 ```
2790 <CodeGroupItem language="CLI">
2791 This workflow needs more logic than a single shell command. Use the [Claude SDK](https://platform.claude.com/docs/en/cli-sdks-libraries/overview) to run it.
2792 </CodeGroupItem>
29612793
29622794 ```python Python
29632795 from typing import Any
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