Configuration and environment

The two credential paths and every environment variable the generated agent reads.

Before you startA generated agent directory with `.env.example`.View as Markdown

Copy .env.example to .env for local runs. __main__.py and every test script load it. In a deployed container, set the same variables as Container Apps secrets and env vars, or pass --env-file to docker run.

Claude credentials: pick one path

Path A: Anthropic API direct

.env

ANTHROPIC_API_KEY=<your-anthropic-api-key>

Path B: Claude on Microsoft Foundry

.env

CLAUDE_CODE_USE_FOUNDRY=1
ANTHROPIC_FOUNDRY_RESOURCE=<your-foundry-resource-name>
ANTHROPIC_FOUNDRY_API_KEY=<your-foundry-resource-key>
ANTHROPIC_API_KEY=<the-same-foundry-resource-key>

ANTHROPIC_FOUNDRY_RESOURCE is the resource name only: no URL, no protocol. The SDK builds https://<name>.services.ai.azure.com/anthropic/ itself.
Set ANTHROPIC_API_KEY to the same value as ANTHROPIC_FOUNDRY_API_KEY. The bundled Claude Code CLI reads that name even in Foundry mode, and the health probe requires it.
The auth header on the wire is Anthropic-style x-api-key, not Azure's api-key.

Every variable

Variable	Default	What it does
`ANTHROPIC_API_KEY`	none	Required on both paths.
`CLAUDE_CODE_USE_FOUNDRY`	unset	`1` switches to Microsoft Foundry.
`ANTHROPIC_FOUNDRY_RESOURCE`	none	Foundry resource name (Path B).
`ANTHROPIC_FOUNDRY_API_KEY`	none	Foundry resource key (Path B).
`AGENT_HOST`	`0.0.0.0`	Bind address (plain-HTTP surface).
`AGENT_PORT`	`{{PORT}}`	Listen port (plain-HTTP surface).
`AGENT_MAX_CONCURRENCY`	`3`	Concurrent `/execute` streams per process.
`CLAUDE_AGENT_CWD`	`/app`	Working directory; the SDK looks for `.claude/skills/` here.
`CLAUDE_AGENT_MODEL`	`claude-sonnet-4-6`	Model id.
`CLAUDE_AGENT_MAX_TURNS`	`50`	Tool-call turns per run. Raise it if you see `approaching cap` warnings; lower it for stricter cost control.
`CLAUDE_AGENT_MAX_BUDGET_USD`	unset (no ceiling)	Hard per-run cost ceiling, passed as `max_budget_usd`.
`CLAUDE_AGENT_EFFORT`	unset (SDK default)	`low`, `medium`, `high`, `xhigh`, or `max`. Other values are ignored.
`CLAUDE_AGENT_MAX_BUFFER_BYTES`	unset (SDK's 1 MiB)	Raise for file-heavy skills, for example `67108864`. See below.
`CLAUDE_CODE_MAX_RETRIES`	`5`	Bounded CLI retries.
`<SKILL>_OUTPUTS_DIR`	`/outputs`	Only if the skill writes files; named by you, for example `REPORT_OUTPUTS_DIR`.
`EMIT_STEP_ACTIVITY_LOG`	your choice	AMC variant only: turns the thinking and tool detail rows on or off.

Important

The SDK frames its stdout at 1 MiB per message. Parallel tool results arrive as one message, so a file-heavy skill can exceed the limit and die with JSON message exceeded maximum buffer size after the orchestration was already paid for. Set CLAUDE_AGENT_MAX_BUFFER_BYTES for those skills.

Env vars for the skill's own scripts

The CLI runs the skill's scripts with the env= dict from ClaudeAgentOptions. Put anything the scripts read there through {{SKILL_ENV_VARS}}, for example "REPORT_OUTPUTS_DIR": OUTPUTS_DIR for a skill that writes files or "REPORT_DIR": "/mnt/report" for one that reads tokens from a mounted share.

Where each value is set

Set in	Values
`Dockerfile` `ENV`	`HOME`, `AGENT_PORT`, `AGENT_HOST`, `CLAUDE_AGENT_CWD`, `CLAUDE_AGENT_MODEL`, and the outputs or token directory variables. Never secrets.
Runtime (secrets)	`ANTHROPIC_API_KEY`, `ANTHROPIC_FOUNDRY_API_KEY`.
Runtime (plain env)	`CLAUDE_CODE_USE_FOUNDRY`, `ANTHROPIC_FOUNDRY_RESOURCE`, and any tuning knob you want to change without a rebuild.

Last updated 2026-10-21