name = "Step 3.5 Flash 2603"
description = "StepFun flash model for efficient multimodal reasoning, coding, and tool use"
release_date = "2026-04-02"
last_updated = "2026-04-02"
attachment = false
reasoning = true
temperature = true
tool_call = true
knowledge = "2025-01"
open_weights = true

# Chat `reasoning_effort` and Messages `output_config.effort` accept low/high
# (accessed 2026-06-25).
# https://platform.stepfun.com/docs/zh/guides/models/step-3.5-flash
[[reasoning_options]]
type = "effort"
values = ["low", "high"]

[interleaved]
field = "reasoning_content"

[cost]
input = 0.10
output = 0.30
cache_read = 0.02

[limit]
context = 256_000
input = 256_000
output = 256_000

[modalities]
input = ["text"]
output = ["text"]