CLI Tools

GitHub Copilot CLI

Use BYOK environment variables to select an OpenAI-compatible provider.

ConfigurableOpenAI Chat CompletionsDocs checked 2026-09-18

The vendor documents custom endpoints. Check model capabilities and verify the connection.

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Before you begin

Use a current Copilot CLI release with BYOK support. The model needs streaming and tool calling; organization policies may restrict features.

Have an A2Agent API key ready and copy an accessible model ID from the catalog. Replace every placeholder, back up existing settings and keep keys out of repositories.

Manage API keys Browse models

Setup

File contents are usually shared; switching OS changes commands and paths. For WSL on Windows, select macOS / Linux.

01Install or update
Follow GitHub’s installation instructions for your OS, then run copilot --version.
Open official documentation

02Configure BYOK

Set these variables in the terminal that launches copilot. Use the exact model ID from the catalog.

Shell

export COPILOT_PROVIDER_BASE_URL='https://a2agent.me/v1'
export COPILOT_PROVIDER_API_KEY='YOUR_A2AGENT_API_KEY'
export COPILOT_PROVIDER_TYPE='openai'
export COPILOT_MODEL='YOUR_MODEL_ID'
copilot

Capabilities and limits

Agent tasks need enough context. Check the model’s context window before choosing it.
This configures the CLI. VS Code has a separate language-model configuration entry.

Verify the connection

Replace every placeholder and run locally. Expect JSON containing OK. Then start a new client conversation, test one read-only tool call separately, and confirm the requests in A2Agent usage records. This test incurs a small amount of model usage.

Shell

curl --fail-with-body --silent --show-error --max-time 60 'https://a2agent.me/v1/chat/completions' \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer YOUR_A2AGENT_API_KEY' \
  -d '{"model":"YOUR_MODEL_ID","max_tokens":128,"messages":[{"role":"user","content":"Reply with OK."}]}'

Troubleshooting

If a managed model is still selected, check that COPILOT_MODEL and provider variables reach the process, and update an older CLI.

401 / 403: authentication or access denied

Use a key issued by A2Agent, without extra spaces, and check that it is active and unexpired. Confirm the group permits the model and protocol. A vendor subscription credential cannot replace an A2Agent key.

404 / model not found: endpoint or model mismatch

Check the root URL, /v1 prefix and full request path against this guide; avoid duplicated paths. Model IDs are case-sensitive and must be accessible to the current key.

429: quota or rate limit

Check your balance, key limits, concurrent usage and service status. Wait before retrying and reduce simultaneous agents; repeated retries do not remove a quota limit.

Chat works, but tools fail or streaming stops

Test a short text request, then a single read-file tool call. Check tool support, output budget, proxy timeouts and client version. Inspect the diff before resuming a long task to avoid repeating actions.

Restore previous settings

Close the terminal, or remove these four COPILOT_ variables from your shell profile and restart.

Sources and check date

Status is based on official configuration docs, not end-to-end client testing with A2Agent.

Docs checked 2026-09-18