Mistral Small 4

Mistral Small 4 is Mistral AI’s compact Open Weights model for general and agentic tasks. The MoE architecture activates only 6.5 billion of the total 119 billion parameters per token, the context window spans 256,000 tokens, and the model processes text and image inputs. Available under the Apache 2.0 license for local use or via the Mistral API, from a European provider environment.

Mistral AI Version 4 Commercial use permitted MoE 119 B (6.5 B active) 256 K Context 01/2026 $0.1 / $0.3 per 1M

  • Open Weights
  • Workstation
  • Mistral AI
  • Text
  • Vision
  • Instruction-Tuned
  • Long Context
  • Real-Time

Tool-use profile: 6 assets in detail

Comparison of asset performance (P1/P2/Combined) against the fleet average

Asset performance (radar)

Score Breakdown vs. Fleet Average


Tool-use details

Asset performance, reliability, and runtime profile

CrucibleMark evaluates tool use across 6 independent tests. Click a test name for details.

Reliability

  • Tool Call Valid: No
  • Retry: Not required
  • Hallucination: Not detected

Reliability measures how consistently a model actually executes tool calls: Tool Call Valid schema and format accepted, Retry Required successful only after retry, Hallucination Flag fabricated tools or parameters detected. All three green means production-ready.

Runtime profile

Call 1
0.98
First Request
MCP
1.32
Protocol Latency
Synthesis
3.29
Response Generation
Total
5.6
Sum of All Phases
Token
1180
Input + Output
Cost
$0
Cost per Run

The runtime profile shows the latency and cost metrics for the model run: Call 1 First Request, MCP Protocol Latency, Synthesis Response Generation, Total sum of all phases, supplemented by Token input and output and Cost cost per run.

Tool-use review

Updated · Instruction-Tuned · Long Context

Deployment Verdict

Do not deploy for autonomous MCP pipelines, as the tool calls are not valid and the combined utility score of 20.33 is clearly too weak despite the absence of hallucinations.

Tool Execution Profile

Mistral Small 4 shows no reliable tool behavior in this run. The core finding is not a single misstep but a systematic absence of usable execution. The EU License Research flow still works, but the model fails across all operational tool disciplines: HTTP Fetch & Extract, Tool Failure Handling (404), Web Search & Tool Selection, URL Construction & Fetch, and Multilingual Search & Synthesis each score P1 at 0.

This is particularly critical for tool selection. In the web search test — which checks without explicit guidance whether a search tool is needed instead of fetch — the model fails to identify the appropriate strategy. In the URL construction test — which requires deriving the target URL from internal knowledge and then fetching it correctly — it likewise delivers no usable execution. This does not look like flexible tool intelligence; it looks like a fragile pattern that only holds under very narrow task guidance. No retry was needed. That argues against a mere formatting issue and more toward weak operational understanding of the tool infrastructure.

Synthesis Fidelity

How well does it consolidate tool results? Only to a limited degree. With P2 39.17, the model produces readable summaries but loses precision and completeness on extraction-heavy tasks. For pipelines where years, designations, or status values must be carried over exactly from tool output, this is insufficient.

Does it stay within the tool result or fall back on training data? In the Honeypot EU License Research test — which is designed to force current license restrictions from web sources — the model remains sufficiently disciplined. P2 60 is not strong, but the more important point is: no detected hallucination. The trust signal is therefore better than the actual work output.

Error Resilience

In the 404 test — which checks for transparent behavior when a fetch fails — the model does not fabricate page content. That is the minimum standard for production, and it is met here. Response quality remains weak at P2 20. The model communicates the error in a way that is inadequate rather than dangerous. For supervised workflows this is acceptable; for autonomous error handling, not yet.

Sovereignty Profile

Locally deployable under Apache 2.0 and therefore sovereignty-friendly. In this benchmark, however, it is not fleet-competitive. The Sovereignty Gap is n/a points below the fleet average of 67.19, as no comparable combined sovereignty distance was reported. What matters in practice: local — yes; production-ready for tool orchestration — no.

Conclusion & Recommendation

Mistral Small 4 is suitable for local, sovereign assistance use cases with human oversight — such as pre-structuring, simple summarization, or UI-adjacent copilot tasks without hard tool requirements. It is not suitable for MCP pipelines that must independently select tools, construct URLs, execute fetch calls correctly, and pass external tool results on with precision. If you hand this model a tool infrastructure, you will need strict external orchestration, validation of every tool transition, and ideally a different model for the actual tool use.

This analysis was generated automatically based on benchmark data. Model used: GPT 4.5 by OpenAI. The raw data and full methodology are documented in the GitHub project.