--- title: "Aider setup with one API key" canonical: https://uplinkswitch.ai/guides/aider generated: 2026-11-04T09:47:45.255Z source: https://uplinkswitch.ai/guides/aider base_url: https://api.uplinkswitch.com/v1 --- [›uplinkswitch](https://uplinkswitch.ai/) [api.uplinkswitch.com/v1](https://uplinkswitch.ai/models)[Console](https://uplinkswitch.ai/console) [›uplinkswitch](https://uplinkswitch.ai/) # Aider Two environment variables, --model openai/, one key for every model. Checked 2026-10-28 ·[All guides](https://uplinkswitch.ai/guides)·[Models](https://uplinkswitch.ai/models) At the end you have aider talking to `https://api.uplinkswitch.com/v1` with one API key from the console and any model id on the [list](https://uplinkswitch.ai/models) after `--model openai/`, Claude included. Each request bills per token to the prepaid balance behind that key; no subscription, and the live table below is the rate on each model today. ## Before you start You need aider installed (`python -m pip install aider-install` then `aider-install`, per its docs), an account on the [console](https://uplinkswitch.ai/console) with credit on it, and one key created there. Create the key for aider alone, so its requests sit apart from any other tool on the Usage page. The base URL and the key are the whole configuration. ## Where the settings are Aider reads an OpenAI-compatible endpoint from two environment variables, `OPENAI_API_BASE` and `OPENAI_API_KEY`, and takes the model as `--model openai/`. The same values can live in `.aider.conf.yml` or `.env`, which aider loads from your home directory, then the root of the git repo, then the current directory; later files win ([aider docs](https://aider.chat/docs/llms/openai-compat.html), read 2026-10-28). ## The config The quick way is to export the two variables and run aider. shell ``` export OPENAI_API_BASE=https://api.uplinkswitch.com/v1 export OPENAI_API_KEY=sk-uplink-live-... cd /to/your/project aider --model openai/claude-sonnet-5-5 ``` To keep it, put the same values in `.aider.conf.yml` in your home directory for every project, or in the repo root for one. ~/.aider.conf.yml ``` model: openai/claude-sonnet-5-5 weak-model: openai/claude-haiku-5-5 openai-api-base: https://api.uplinkswitch.com/v1 openai-api-key: sk-uplink-live-... ``` Or a `.env` file in the same places, with the names from aider's sample file: `AIDER_OPENAI_API_BASE` for the base URL and `OPENAI_API_KEY` for the key. .env ``` AIDER_OPENAI_API_BASE=https://api.uplinkswitch.com/v1 OPENAI_API_KEY=sk-uplink-live-... AIDER_MODEL=openai/claude-sonnet-5-5 ``` ## Which model id to use Any chat id on the [Models page](https://uplinkswitch.ai/models), written as `openai/`. The Claude ids answer the OpenAI format as well as the Anthropic one, so `openai/claude-sonnet-5-5` goes in the same flag as `openai/gpt-6.1-sol` or `openai/deepseek-v4-pro-0813`. The ids in the table below are the ones that fit an editing agent: every one takes tool calls and long context. `weak-model` handles commit messages and chat history summaries and `editor-model` the editor tasks; both take the same `openai/` form, and their defaults follow the main model (aider docs, read 2026-10-28). ## Price per token | Model | Input / 1M | Output / 1M | Cached / 1M | List input | List output | Under list | | --- | --- | --- | --- | --- | --- | --- | | [Claude Sonnet 5.5](https://uplinkswitch.ai/models/claude-sonnet-5-5) | $1.20 | $3.00 | $0.075 | $2.00 | $10.00 | 40% on input | | [Claude Opus 5.5](https://uplinkswitch.ai/models/claude-opus-5-5) | $2.80 | $10.00 | $0.15 | $4.00 | $20.00 | 30% on input | | [GPT-6.1 Sol](https://uplinkswitch.ai/models/gpt-6.1-sol) | $0.60 | $3.00 | $0.06 | $2.00 | $10.00 | 70% on input | | [Gemini 3.1 Pro Preview](https://uplinkswitch.ai/models/gemini-3.1-pro-preview) | $1.20 | $7.20 | $0.12 | $2.00 | $12.00 | 40% on input | | [DeepSeek V4 Pro 0813](https://uplinkswitch.ai/models/deepseek-v4-pro-0813) | $0.792 | $1.188 | $0.0625 | $1.32 | $3.96 | 40% on input | | [Kimi K3](https://uplinkswitch.ai/models/kimi-k3) | $0.90 | $4.50 | $0.12 | $3.00 | $15.00 | 70% on input | USD per million tokens, live from GET /v1/catalog. List: the developer’s own published price. Cached input bills at the cached rate by itself; aider has no switch to set for it here. Aider sends a repo map along with each request (aider docs, read 2026-10-28), so the input column decides what a session costs. The [Claude Code pricing post](https://uplinkswitch.ai/blog/claude-code-api-cost) works an hour, a day and a month of agent turns at these rates. ## Name the app in the usage log Aider passes custom headers through `extra_params.extra_headers` in `.aider.model.settings.yml`, and the special name `aider/extra_params` applies them to every model (aider docs, read 2026-10-28). Two headers name the app on each request's usage record: .aider.model.settings.yml ``` - name: aider/extra_params extra_params: extra_headers: HTTP-Referer: https://uplinkswitch.ai X-Title: Aider ``` The file goes in the same three places as `.aider.conf.yml`, or anywhere with `--model-settings-file`. ## Model metadata, so aider knows the limits and costs Aider does not know these ids, so it prints "Unknown context window size and costs, using sane defaults" and treats the model as free with unlimited context. Requests work either way. To give it the real figures, save this as `.aider.model.metadata.json` next to the config file. The costs are per token at today's live rate; the limits are the developer's published ones where the catalog has them. .aider.model.metadata.json ``` { "openai/claude-sonnet-5-5": { "max_input_tokens": 1000000, "max_tokens": 128000, "max_output_tokens": 128000, "input_cost_per_token": 0.0000012, "output_cost_per_token": 0.000003, "litellm_provider": "openai", "mode": "chat" }, "openai/claude-opus-5-5": { "max_input_tokens": 1000000, "max_tokens": 128000, "max_output_tokens": 128000, "input_cost_per_token": 0.0000028, "output_cost_per_token": 0.00001, "litellm_provider": "openai", "mode": "chat" }, "openai/gpt-6.1-sol": { "max_input_tokens": 1050000, "max_tokens": 128000, "max_output_tokens": 128000, "input_cost_per_token": 6e-7, "output_cost_per_token": 0.000003, "litellm_provider": "openai", "mode": "chat" }, "openai/gemini-3.1-pro-preview": { "max_input_tokens": 1048576, "max_tokens": 65536, "max_output_tokens": 65536, "input_cost_per_token": 0.0000012, "output_cost_per_token": 0.0000072000000000000005, "litellm_provider": "openai", "mode": "chat" }, "openai/deepseek-v4-pro-0813": { "max_input_tokens": 1048576, "max_tokens": 393216, "max_output_tokens": 393216, "input_cost_per_token": 7.92e-7, "output_cost_per_token": 0.0000011879999999999999, "litellm_provider": "openai", "mode": "chat" }, "openai/kimi-k3": { "max_input_tokens": 1048576, "max_tokens": 1048576, "max_output_tokens": 1048576, "input_cost_per_token": 9.000000000000001e-7, "output_cost_per_token": 0.0000045, "litellm_provider": "openai", "mode": "chat" } } ``` With it in place, aider's own cost line after each turn uses the live rates, and it knows the context window of the model. ## Check it From a shell, the key should list the models: shell ``` curl https://api.uplinkswitch.com/v1/models -H "Authorization: Bearer $OPENAI_API_KEY" ``` Then start aider and send one message. The request shows on the [console](https://uplinkswitch.ai/console) Usage page within seconds, with its tokens and charge. ## Errors you will see - `401 invalid_api_key`: the key is wrong or revoked, or `OPENAI_API_KEY` is unset in this shell. Copy it again from the console. - `402 insufficient_balance`: the balance does not cover the request. Top up in the console. - `402 monthly_limit_reached`: the key hit the monthly spend limit you set on it. Raise it in the console, or wait for the first of the month. - `404 model_not_found`: the part after `openai/` is not on the Models page. Copy the id from the page rather than typing it: a dot, a dash or a date suffix out of place is enough. - `403 scope_denied`: the key carries a model allowlist and this id is not on it. - `429 rate_limited`: the key hit its per-minute or concurrency limit. The response carries `retry-after` in seconds. - "Missing these environment variables": aider could not find `OPENAI_API_BASE` or `OPENAI_API_KEY`. Export them, or put them in `.env`; on Windows restart the terminal after `setx`. - "Unknown context window size and costs": a warning, not an error. The metadata file above removes it. ## The same key in other agents [Claude Code](https://uplinkswitch.ai/guides/claude-code) takes two environment variables; [OpenCode](https://uplinkswitch.ai/guides/opencode) and [OpenClaw](https://uplinkswitch.ai/guides/openclaw) read a provider block; [Cline](https://uplinkswitch.ai/guides/cline) and [Kilo Code](https://uplinkswitch.ai/guides/kilo-code) take the base URL and key in a settings panel. One balance serves all of them, and a key per tool keeps the spend apart in the console. ## Questions ### Yes. Set OPENAI\_API\_BASE to https://api.uplinkswitch.com/v1, OPENAI\_API\_KEY to your key, and run aider --model openai/claude-sonnet-5-5 or openai/claude-opus-5-5. The Claude ids answer the OpenAI chat completions format here, so aider needs no Anthropic variables. ### Export OPENAI\_API\_BASE, or put openai-api-base in .aider.conf.yml, or AIDER\_OPENAI\_API\_BASE in a .env file next to your project (aider docs, read 2026-10-28). All three take the same value, https://api.uplinkswitch.com/v1, with /v1 on the end. ### It tells aider to send the request in the OpenAI format to whatever OPENAI\_API\_BASE points at. The part after the slash is sent as the model field, so it must be an id from the Models page, exactly as written there. ### Aider prints "Unknown context window size and costs, using sane defaults" for any id it has no metadata for (aider docs, read 2026-10-28). The requests still work. The .aider.model.metadata.json block on this page gives aider the figures so the warning stops and its cost line uses the live rates. ### Each request bills per token at the live rate in the table above, $1.20 in and $3.00 out per million on Claude Sonnet 5.5 today. Every request shows on the console Usage page within seconds with its tokens and its charge in dollars, filterable by key and model. ### Aider uses the weak model for commit messages and chat history summaries, so a small fast id is enough. Any chat id on the Models page works; set it as openai/ in .aider.conf.yml or with --weak-model. Get a key in the [console](https://uplinkswitch.ai/console): prepaid credit, no subscription, 30-day price lock. ## Related - [Claude Code pricing](https://uplinkswitch.ai/blog/claude-code-api-cost) - [Claude Code alternatives compared](https://uplinkswitch.ai/blog/claude-code-alternatives) - [Codex CLI setup](https://uplinkswitch.ai/guides/codex-cli) - [Claude Code setup](https://uplinkswitch.ai/guides/claude-code) - [OpenHands setup](https://uplinkswitch.ai/guides/openhands) - [Claude Haiku 5.5](https://uplinkswitch.ai/models/claude-haiku-5-5) - [Claude Sonnet 5.5](https://uplinkswitch.ai/models/claude-sonnet-5-5) - [GPT-5.3-Codex](https://uplinkswitch.ai/models/gpt-5.3-codex) - [Kimi K2.7 Code](https://uplinkswitch.ai/models/kimi-k2.7-code) - [GLM 5.3](https://uplinkswitch.ai/models/glm-5.3) - [Claude API pricing](https://uplinkswitch.ai/pricing/claude) - [GPT API pricing](https://uplinkswitch.ai/pricing/gpt) - [Kimi API pricing](https://uplinkswitch.ai/pricing/kimi) - [GLM API pricing](https://uplinkswitch.ai/pricing/glm)