ModelSpec is an analysis of alternatives for AI models: it decides which models fit a job from your requirements, sourced benchmarks and real cost, and shows its work.

Gemini 2.5 Flash vs Gemini 3.8 Flash for General assistant on a budget, as of 2026-09-23

Find an active assistant that keeps one task at or under $0.05 without ignoring response quality.

Worked example as of 2026-09-23, from the public data image.

What the evidence says

The evidence separates them: Gemini 3.8 Flash leads for General assistant on a budget, with a 58% chance of being the best model in the full lineup for this job, as of 2026-09-23.

Gemini 2.5 Flash has a 15% chance of matching or beating Gemini 3.8 Flash on this job's objective.

probability bands: a model joins the leader when P(its score >= the leader's) >= 0.25 under the score posteriors; a weighted capability with an 80% interval wider than 2.8 is not enough evidence

Decision status: partial. P(best) and score intervals retain the full ranked lineup for this job, including models beyond this pair and models with thin evidence. Models with unknown objective values remain unranked and are outside this probability. P(best) is not a head-to-head probability. Separation from this challenger need not mean a unique best model across that lineup.

Scores and score intervals use the objective's dimensionless normalised units. Cost per task is in USD for the selected offering and the applied spec's task size. When task size is omitted, the engine uses its documented default. Unavailable means the engine returned no value.

At most $0.05 a task; quality still ranked.

Requirements

• model.class = text-generator: A conversational assistant needs a text-generating model.
• model.lifecycle = active: An active model is still supported by its lab or provider.
• offering.cost_per_task <= 0.05: The offering must stay within the per-task budget.

Preferences

• chat_preference: Prefer stronger assistants among offerings inside the budget.
• -offering.cost_per_task: Prefer the cheaper task among offerings inside the budget.

Evidence for Gemini 2.5 Flash

Missing facts for Gemini 2.5 Flash

• feature.streaming: not_disclosed
• licence.commercial_use: not_disclosed
• licence.fine_tuning: not_disclosed
• licence.output_training: not_disclosed
• licence.user_cap: not_disclosed
• model.context_window: not_disclosed
• model.fits_hardware: unknown
• model.hardware_fit_indeterminate: unknown
• model.input_modalities: not_disclosed
• model.languages: unknown
• model.max_output_tokens: not_disclosed
• model.output_modalities: not_disclosed
• model.parameters_total: unknown
• model.release_date: not_disclosed
• model.weights_openness: not_disclosed
• origin.base_lineage: not_disclosed
• origin.lab_jurisdiction: not_disclosed
• origin.weights_hosting: not_disclosed
• offering.api_model_id: unknown
• offering.attestation.baa: not_disclosed
• offering.attestation.soc2: not_disclosed
• offering.data.retention: not_disclosed
• offering.data.trains_on_customer_data: not_disclosed
• offering.data.zero_retention: not_disclosed
• offering.private_deployment: unknown
• offering.router_slug: unknown
• offering.speed.throughput: unknown
• offering.speed.time_to_first_token: unknown

Evidence for Gemini 3.8 Flash

Missing facts for Gemini 3.8 Flash

• model.hardware_fit_indeterminate: unknown
• model.languages: unknown
• model.parameters_total: unknown
• origin.base_lineage: not_disclosed
• origin.weights_hosting: not_disclosed
• offering.api_model_id: unknown
• offering.attestation.baa: not_disclosed
• offering.attestation.soc2: not_disclosed
• offering.private_deployment: unknown
• offering.router_slug: unknown
• offering.speed.throughput: unknown
• offering.speed.time_to_first_token: unknown

What this template teaches

The budget is a Must; inside it, cost and quality share the ranking equally.

Decision dec_31e56e608d050b9f9287f060 on public snapshot snap_05a963d2477ac2fb.

Read the full dated job answer.

The live board uses current data. This link applies the template to its full lineup.

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