Agent assignment credential validation failed: Bad credentials (HTTP 401). Agent assignment credential source: GH_AW_AGENT_TOKEN. Dedicated assignment credential: present. Credential format: fine-grained PAT (validity and permissions unverified). Configure GH_AW_AGENT_TOKEN or assign-to-agent.github-token with a valid user token: a fine-grained PAT with metadata: read and actions, contents, issues, and pull requests: write, or a classic PAT with repo scope. Check token expiry, repository access, and organization approval/SSO. GitHub App installation tokens, including GITHUB_TOKEN, cannot assign Copilot. See https://github.github.com/gh-aw/reference/copilot-cloud-agent/#authentication

"The ubuntu-latest label will migrate to Ubuntu 26 beginning October 19, 2026. For more information, see https://github.com/actions/runner-images/issues/14748"

"The ubuntu-latest label will migrate to Ubuntu 26 beginning October 19, 2026. For more information, see https://github.com/actions/runner-images/issues/14748"