Sakana: Fugu Ultra v2

sakana/fugu-ultra-v2 · SakanaNot yet established

Declared family: Unknown
Evidence confidence: Unknown
Declared tokenizer tag: Other
Entered catalogue: 11 September 2026
Last tested: Not yet measured
Measurement: Awaiting measurement

Evidence stack

Signals of different kinds, weighed together

Signal	Result	Reference
Tokenizer signature	Not measured	–
API surface	Identical contract to 1 other entry	api_956e60ef
Context and output	1,000,000 context · 128,000 max output	declared
Reasoning contract	Mandatory · efforts max, xhigh, high · default xhigh	declared
Serving providers observed	None recorded yet	–

Declared record

What the catalogue claims about this model

Fugu Ultra v2 is the higher-performance model in Sakana AI's Fugu family. Rather than a single monolithic model, Fugu is a learned multi-agent orchestration system: a language model trained to...

Modalities: text+image+file->text
Declared tokenizer: Other
Prompt price: $5.00 / M tokens
Completion price: $30.0 / M tokens

Supported parameters

include_reasoningreasoningreasoning_effortstructured_outputstool_choicetoolsweb_search_options

defaults: {"temperature":null,"top_p":null,"top_k":null,"frequency_penalty":null,"presence_penalty":null,"repetition_penalty":null}

Catalogue entry

History

Every observation, kept as taken

11 September 2026Enters the OpenRouter catalogue with no declared family.

Cite this page as the evidence record for Sakana: Fugu Ultra v2: the URL is stable, measurements are dated, and revisions append to the history above. Method: tokenizer fingerprinting, v1, 50 strings.