# Claude Sonnet 4.5Thinking

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Anthropic

Canonical URL: https://benchize.com/models/claude-sonnet-4-5-thinking
Last updated: Thu, 22 Oct 2026 07:32:33 GMT

Reproduction and quotation must name Benchize, link to the canonical HTML URL, and retain individual source citations.

Anthropic

## Benchmarks

| Benchmark | Score | ± | Rank | Cost | Source |  |
| --- | --- | --- | --- | --- | --- | --- |
| [MCP Atlas](https://benchize.com/benchmarks/scale%3Amcp_atlas.md) | 59.5source score | CI 56.4–62.6 | 17 / 22 | — | [scale](https://labs.scale.com/leaderboard/mcp_atlas) |  |
| ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `score` \| 59.5 \| source_score \| reported \| Higher is better \| ### Configuration Reasoning effort unknown Model configuration claude-sonnet-4-5 (thinking) sourceModelVersion Not reported thinkingEnabled true ### Reported statistics Uncertainty Confidence interval: 56.4–62.6 contaminationWarning Not reported rank 28 reportedConfidenceHalfWidth 3.1 ### Source [Original source](https://labs.scale.com/leaderboard/mcp_atlas) Source scale Original model label claude-sonnet-4-5 (thinking) Observed 2026-10-22T03:30:07.875Z Evidence SHA-256 `7b0bc178e35a1688340e9efca5795a8f54d07e56a98f9cacd5e4471e0da266e9` Source locator `/rows/27` |  |  |  |  |  |  |
| [τ-bench banking knowledge](https://benchize.com/benchmarks/sierra%3Abanking_knowledge.md) | 25.26% | — | 14 / 19 | $4.05 | [sierra](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) |  |
| ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `pass_1` \| 25.26 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_2` \| 15.81 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_3` \| 12.63 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_4` \| 10.31 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `cost` \| 4.04814 \| USD \| source_reported \| Lower is better \| ### Configuration benchmarkVersion 1.0.1 harness tau-bench methodology {"evaluation_date":"2026-02-24","notes":"Evaluated using Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) with extended thinking enabled. User simulator: gpt-5.2 with reasoning_effort: low. 4 trials. Seed: 300. Banking domain evaluated with terminal-based agentic search retrieval. banking_knowledge re-graded under tau2-bench v1.0.1 grading fixes on 2026-07-15 (extra-read logging #329, numeric-argument normalization #397, T077-T086 gold trajectories #402); scores prior to v1.0.1 are not comparable.","tau2_bench_version":"1.0.1","user_simulator":"gpt-5.2","verification":{"details":"Verified evaluation with full trajectory data available. Standard tau-bench scaffold.","modified_prompts":false,"omitted_questions":false}} modality text Reasoning effort enabled retrieval terminal sourceSubmission claude-sonnet-4-5_sierra_2026-02-26 ### Source [Original source](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) Source sierra Original model label Claude Sonnet 4.5 Evaluated 2026-02-26 Observed 2026-10-21T16:54:47.167Z Evidence SHA-256 `e5ce9f12ab9e616db52e973e90b48144b7bafd29e35c4fd6c3e7fde573a9b8d8` Source locator `/results/banking_knowledge` |  |  |  |  |  |  |
| [τ-bench retail](https://benchize.com/benchmarks/sierra%3Aretail.md) | 72.37% | — | 8 / 8 | $0.25 | [sierra](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) |  |
| ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `pass_1` \| 72.37 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_2` \| 57.46 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_3` \| 47.37 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_4` \| 39.47 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `cost` \| 0.25494 \| USD \| source_reported \| Lower is better \| ### Configuration benchmarkVersion 1.0.1 harness tau-bench methodology {"evaluation_date":"2026-02-24","notes":"Evaluated using Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) with extended thinking enabled. User simulator: gpt-5.2 with reasoning_effort: low. 4 trials. Seed: 300. Banking domain evaluated with terminal-based agentic search retrieval. banking_knowledge re-graded under tau2-bench v1.0.1 grading fixes on 2026-07-15 (extra-read logging #329, numeric-argument normalization #397, T077-T086 gold trajectories #402); scores prior to v1.0.1 are not comparable.","tau2_bench_version":"1.0.1","user_simulator":"gpt-5.2","verification":{"details":"Verified evaluation with full trajectory data available. Standard tau-bench scaffold.","modified_prompts":false,"omitted_questions":false}} modality text Reasoning effort enabled retrieval Not reported sourceSubmission claude-sonnet-4-5_sierra_2026-02-26 ### Source [Original source](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) Source sierra Original model label Claude Sonnet 4.5 Evaluated 2026-02-26 Observed 2026-10-21T16:54:47.167Z Evidence SHA-256 `e5ce9f12ab9e616db52e973e90b48144b7bafd29e35c4fd6c3e7fde573a9b8d8` Source locator `/results/retail` |  |  |  |  |  |  |
| [τ-bench airline](https://benchize.com/benchmarks/sierra%3Aairline.md) | 72% | — | 7 / 8 | $0.3 | [sierra](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) |  |
| ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `pass_1` \| 72 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_2` \| 62 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_3` \| 54.5 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_4` \| 48 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `cost` \| 0.29646 \| USD \| source_reported \| Lower is better \| ### Configuration benchmarkVersion 1.0.1 harness tau-bench methodology {"evaluation_date":"2026-02-24","notes":"Evaluated using Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) with extended thinking enabled. User simulator: gpt-5.2 with reasoning_effort: low. 4 trials. Seed: 300. Banking domain evaluated with terminal-based agentic search retrieval. banking_knowledge re-graded under tau2-bench v1.0.1 grading fixes on 2026-07-15 (extra-read logging #329, numeric-argument normalization #397, T077-T086 gold trajectories #402); scores prior to v1.0.1 are not comparable.","tau2_bench_version":"1.0.1","user_simulator":"gpt-5.2","verification":{"details":"Verified evaluation with full trajectory data available. Standard tau-bench scaffold.","modified_prompts":false,"omitted_questions":false}} modality text Reasoning effort enabled retrieval Not reported sourceSubmission claude-sonnet-4-5_sierra_2026-02-26 ### Source [Original source](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) Source sierra Original model label Claude Sonnet 4.5 Evaluated 2026-02-26 Observed 2026-10-21T16:54:47.167Z Evidence SHA-256 `e5ce9f12ab9e616db52e973e90b48144b7bafd29e35c4fd6c3e7fde573a9b8d8` Source locator `/results/airline` |  |  |  |  |  |  |
| [τ-bench telecom](https://benchize.com/benchmarks/sierra%3Atelecom.md) | 84.87% | — | 6 / 8 | $0.49 | [sierra](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) |  |
| ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `pass_1` \| 84.87 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_2` \| 75.44 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_3` \| 68.86 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `pass_4` \| 64.04 \| percent \| consistent_success_across_k_trials \| Higher is better \| \| `cost` \| 0.48769 \| USD \| source_reported \| Lower is better \| ### Configuration benchmarkVersion 1.0.1 harness tau-bench methodology {"evaluation_date":"2026-02-24","notes":"Evaluated using Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) with extended thinking enabled. User simulator: gpt-5.2 with reasoning_effort: low. 4 trials. Seed: 300. Banking domain evaluated with terminal-based agentic search retrieval. banking_knowledge re-graded under tau2-bench v1.0.1 grading fixes on 2026-07-15 (extra-read logging #329, numeric-argument normalization #397, T077-T086 gold trajectories #402); scores prior to v1.0.1 are not comparable.","tau2_bench_version":"1.0.1","user_simulator":"gpt-5.2","verification":{"details":"Verified evaluation with full trajectory data available. Standard tau-bench scaffold.","modified_prompts":false,"omitted_questions":false}} modality text Reasoning effort enabled retrieval Not reported sourceSubmission claude-sonnet-4-5_sierra_2026-02-26 ### Source [Original source](https://sierra-tau-bench-public.s3.us-west-2.amazonaws.com/submissions/claude-sonnet-4-5_sierra_2026-02-26/submission.json) Source sierra Original model label Claude Sonnet 4.5 Evaluated 2026-02-26 Observed 2026-10-21T16:54:47.167Z Evidence SHA-256 `e5ce9f12ab9e616db52e973e90b48144b7bafd29e35c4fd6c3e7fde573a9b8d8` Source locator `/results/telecom` |  |  |  |  |  |  |

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Cite as: Claude Sonnet 4.5Thinking — Benchize, https://benchize.com/models/claude-sonnet-4-5-thinking (retrieved 2026-10-22)