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Choosing US-only inference for Kimi K3 costs about 11% more than Bedrock's global profile

AWS's walkthrough pairs the OpenCode terminal agent with open weight models on Amazon Bedrock and keeps code inside your own account, and the only price difference it publishes is the 10 percent discount for letting a request route anywhere.

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Illustration accompanying Choosing US-only inference for Kimi K3 costs about 11% more than Bedrock's global profile

What happened

  • AWS published a walkthrough for running the OpenCode agent on a developer's machine against open weight models on Amazon Bedrock, with inference inside the customer's own AWS account and no per-seat fees.
  • The coding examples use Moonshot AI Kimi K3, OpenAI GPT-OSS 120B and NVIDIA Nemotron 3 Super 120B, all served through Bedrock.
  • AWS says global cross-Region inference costs approximately 10 percent less than a geographic profile.
  • The post says Ethara.AI already runs this architecture in production with multi-agent orchestration for AI engineering and research workflows.

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Why it matters

  • decision Compliance stops being a configuration detail: the cheapest routing is the one that lets requests leave the geography, so whoever owns the residency clause is signing off on a recurring per-token premium.
  • cost Spend moves from headcount to retries. A noisy agent loop, not a new hire, is what raises next month's bill, and the 5-to-30-times multiplier lands on the AWS account hosting the inference.
  • constraint Below millions of conversations a month the choice is unpriced, so a small team has to instrument its own token spend before it can compare consumption billing with what it pays per seat today.
  • capability Governance for a coding agent collapses into the IAM, CloudTrail and PrivateLink setup a team already operates, with no separate vendor audit path to negotiate.

Two strings carry most of the cost decision. For workloads with no regional restriction, AWS recommends the global profile `global.moonshotai.kimi-k3`, which sends each request to any supported commercial AWS Region worldwide [7]. The US geographic profile, `us.moonshotai.kimi-k3`, keeps processing inside the US geography for data residency requirements [8]. Read the 10 percent discount from the other end and the residency choice costs roughly 11 percent more per request: if global is 0.90 of geographic, geographic is 1 divided by 0.90 [10]. That premium applies to every token the agent spends, including the ones it spends re-reading a file it read two turns ago.

The token multiplier is the other half. AWS cites Gartner's 2026 analysis putting agentic workflows at 5 to 30 times the token consumption of ordinary use [15]. Consumption pricing removes the per-seat floor and replaces it with a bill that tracks how often the agent retries.

What you run locally is a Go binary [1]. It edits files, runs shell commands, and reads project structure through Language Server Protocol diagnostics [2], and it speaks to more than 75 model providers, Bedrock among them [3]. Inference happens inside your AWS account, with no GPU provisioning and no inference infrastructure to manage [4][20]. Access rules are IAM policies, the audit trail is CloudTrail, the network path can be PrivateLink, and encryption controls are the same ones proprietary models on Bedrock inherit [14]. Bedrock is in scope for HIPAA, SOC 2, ISO 27001, FedRAMP and GDPR [13].

The performance argument leans on one number from someone else's workload. AWS cites CrowdStrike's fine-tuned NVIDIA Nemotron at 96 percent valid query accuracy, against GPT-4o at 61 percent and Claude Sonnet 4.5 at 94 percent [17]. That is not one experiment: the winning model was fine-tuned on CrowdStrike's domain, and the metric is whether a generated query is valid, not whether a patch compiles. The margin over Sonnet 4.5 is two points [21]. For the figure to transfer to your repository you would need labelled data in your own domain, a fine-tuning run, and a validity metric that predicts working code; the walkthrough's Nemotron 3 Super 120B is served stock from Bedrock [5].

AWS scopes its cost claim narrowly: at the order of multimillion conversations per month, switching to open weight models on Bedrock can reduce annualized costs [16]. The post does not publish a per-seat comparison, and the thing it argues against is per-seat subscriptions charged regardless of how much you use them [19]. McKinsey's 2025 open-source report, also cited, says 76 percent of organizations expect to increase open source AI usage and that leading AI adopters are 40 percent more likely to use open weight models [18]. That report measures expectation, not deployments. A team with a residency clause gets what it needs from the profile ID and its existing IAM and logging [12]. A team hoping to cut a seat bill has to measure its own token volume first.

What to watch

  • Whether AWS publishes a token-level cost example for an OpenCode session at team scale, instead of the multimillion-conversation case.
  • Whether other open weight models on Bedrock get the same global and geographic profile pair, and whether the 10 percent gap holds for them.
  • Whether Ethara.AI, named in the post as running this architecture in production, publishes its per-task model routing and spend.
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