Configuration¶
Paperless MCP reads all configuration from environment variables. Domain
variables carry the PAPERLESS_MCP_ prefix; a few third-party variables
(FASTMCP_*, PUID/PGID) keep their upstream names.
This page is the complete reference: every variable the server reads appears
in exactly one table below. The tables come from the same source as
.env.example, the packaged env files, and the
configuration generator, so the four cannot
disagree. The README carries a hand-picked subset of these variables as its
quick entry point.
Server¶
Transport, identity, and tool visibility. PAPERLESS_MCP_SERVER_NAME
identifies the deployment, PAPERLESS_MCP_INSTANCE_DESCRIPTION
distinguishes its material or responsibility for routing, and
PAPERLESS_MCP_INSTRUCTIONS_EXTRA supplies deployment-specific behavioral
policy. The legacy PAPERLESS_MCP_INSTRUCTIONS replaces all generated text,
ignores both additive variables, and logs a deprecation warning at startup.
Generated guidance targets 1,536 UTF-16 units, reserving 512 units for normal operator routing and policy within Claude Code's known 2,048-unit limit. Crossing either threshold logs a warning; startup continues and the server does not truncate the instructions.
The generated guidance names the Paperless instance this deployment fronts,
taking the URL from PAPERLESS_MCP_PAPERLESS_PUBLIC_URL or, unset, from
PAPERLESS_MCP_PAPERLESS_URL. A model can then recognise a link to that
instance and read the document id out of it.
PAPERLESS_MCP_TOOLS_ALLOW and PAPERLESS_MCP_TOOLS_DENY trim which
tools an instance exposes. Hidden tools disappear from tools/list and are
rejected on tools/call; resources and prompts are unaffected. Setting both
variables, or setting one to a value with no names in it, is a startup error.
A name matching no registered tool is ignored, but an allowlist that matches
nothing logs a startup warning, since the instance then exposes zero tools.
See fastmcp-pvl-core's README for the full semantics.
PAPERLESS_MCP_HEALTH_DETAIL decides how much the unauthenticated /health
and /health/ready bodies say, since anyone who can reach the port can read
them: status alone, the default standard with the server name, version and
a verdict per readiness check, or full with a redacted reason for each check
that raised. See Docker deployment for the
routes themselves.
| Variable | Default | Description |
|---|---|---|
PAPERLESS_MCP_TRANSPORT |
stdio |
Transport the server speaks: stdio for local Claude Desktop/Code, http or sse for a network server. |
PAPERLESS_MCP_HOST |
127.0.0.1 |
Interface the HTTP server binds to. |
PAPERLESS_MCP_PORT |
8000 |
TCP port for the HTTP server. |
PAPERLESS_MCP_SHUTDOWN_GRACE_S |
3 |
Seconds SIGTERM may spend draining in-flight requests before the HTTP server exits. Keep it at or below the termination grace period the orchestrator allows. 0 drops in-flight requests immediately. |
PAPERLESS_MCP_BASE_URL |
(none) | Public base URL of the deployed server (https://mcp.example.com). Required for OIDC. Also the fallback source of the MCP Apps domain when app_domain is unset. |
PAPERLESS_MCP_TOOLS_ALLOW |
(none) | Comma-separated explicit tool names this instance exposes; every other tool is hidden from listings and cannot be invoked. Names matching no registered tool are inert. Mutually exclusive with tools_deny. Takes effect through apply_tool_visibility. |
PAPERLESS_MCP_TOOLS_DENY |
(none) | Comma-separated explicit tool names hidden from this instance (absent from listings, cannot be invoked). Names matching no registered tool are inert. Mutually exclusive with tools_allow. Takes effect through apply_tool_visibility. |
PAPERLESS_MCP_SERVER_NAME |
(none) | Rename this server instance; defaults to the project name. |
PAPERLESS_MCP_INSTANCE_DESCRIPTION |
(none) | Concise routing context that distinguishes this deployment's material or responsibility. |
PAPERLESS_MCP_INSTRUCTIONS_EXTRA |
(none) | Deployment-specific behavioral policy added to the generated MCP instructions. |
PAPERLESS_MCP_INSTRUCTIONS |
(none) | Legacy: replaces all generated MCP instructions (deprecated; use _INSTANCE_DESCRIPTION for routing and _INSTRUCTIONS_EXTRA for policy). |
PAPERLESS_MCP_HTTP_PATH |
/mcp |
Mount path for the MCP endpoint; the health routes derive their prefix from it. |
PAPERLESS_MCP_HEALTH_DETAIL |
standard |
How much the unauthenticated /health and /health/ready bodies say: status, standard (adds name, version and per-check verdicts), or full (adds redacted reasons; trusted networks only). |
Authentication¶
Callers authenticate with a bearer token, with OIDC, or with both. OIDC
itself has two modes. remote validates tokens locally against the
provider's JWKS and needs only PAPERLESS_MCP_BASE_URL and
PAPERLESS_MCP_OIDC_CONFIG_URL. oidc-proxy runs the OAuth flow
itself and also needs PAPERLESS_MCP_OIDC_CLIENT_ID and
PAPERLESS_MCP_OIDC_CLIENT_SECRET, registered with the provider as a
confidential client whose redirect URI points at this server.
The Required column below marks the oidc-proxy set. Setting all four
selects that mode and omitting the two client credentials selects remote,
so PAPERLESS_MCP_AUTH_MODE is the way to state the choice rather than
leave it to be inferred. With none of these set, the server starts and
serves unauthenticated. See the authentication guide
for setup, mapped multi-subject tokens, and troubleshooting.
| Variable | Default | Required | Description |
|---|---|---|---|
PAPERLESS_MCP_BEARER_TOKEN |
(none) | No | Single shared bearer token; enables bearer auth unless bearer_tokens_file is set, which takes precedence. |
PAPERLESS_MCP_OIDC_CONFIG_URL |
(none) | Yes | OIDC discovery document URL (https://auth.example.com/.well-known/openid-configuration). |
PAPERLESS_MCP_OIDC_CLIENT_ID |
(none) | Yes | OIDC client identifier registered with the provider. |
PAPERLESS_MCP_OIDC_CLIENT_SECRET |
(none) | Yes | OIDC client secret registered with the provider. |
PAPERLESS_MCP_OIDC_AUDIENCE |
(none) | No | Expected aud claim; tokens issued for another audience are rejected. |
PAPERLESS_MCP_OIDC_REQUIRED_SCOPES |
openid |
No | Scopes a caller must present, space- or comma-separated. Defaults to openid in oidc-proxy mode. |
PAPERLESS_MCP_OIDC_ADVERTISED_SCOPES |
openid offline_access |
No | Scopes advertised to MCP clients in protected-resource metadata, space- or comma-separated. Overrides the default openid offline_access; oidc_required_scopes is always added on top. Set this when the registered client is not permitted offline_access, or to have clients request extra claim scopes (such as groups) without also requiring them in every token. |
PAPERLESS_MCP_OIDC_JWT_SIGNING_KEY |
derived |
No | Signing key for issued tokens; used in oidc-proxy mode only. When unset, the key is derived deterministically from oidc_client_secret, so tokens survive a restart. Rotating that secret then invalidates every issued token. Set this explicitly to decouple token validity from secret rotation. Generate with openssl rand -hex 32. |
PAPERLESS_MCP_OIDC_VERIFY_ACCESS_TOKEN |
false |
No | Validate the access token instead of the id token. |
PAPERLESS_MCP_AUTH_MODE |
(none) | No | Explicit auth-mode override, accepting remote or oidc-proxy (case- and whitespace-insensitive). When unset the mode is auto-detected from which auth variables are set; the override exists because having all four OIDC variables set is ambiguous between those two modes. Other values are ignored with a warning. |
PAPERLESS_MCP_BEARER_TOKENS_FILE |
(none) | No | Path to a TOML file mapping bearer tokens to subjects; overrides the single-token bearer_token mode. |
PAPERLESS_MCP_BEARER_DEFAULT_SUBJECT |
bearer-anon |
No | Subject assigned to the single-token bearer mode; ignored when bearer_tokens_file is set, since mapped mode carries per-token subjects. |
Persistence¶
One URL configures every stateful subsystem. A redis://
PAPERLESS_MCP_KV_STORE_URL is also reused for background tasks when
PAPERLESS_MCP_TASKS_URL is unset, so a single URL covers both.
| Variable | Default | Description |
|---|---|---|
PAPERLESS_MCP_KV_STORE_URL |
file:///data/state |
Persistent-state backend URL shared by every pvl-core subsystem that needs state. memory:// is in-process and lost on restart; file:///path persists on one server; redis://, dynamodb:// and mongodb:// each need their matching extra. When unset, defaults to file:///data/state (the volume family Docker images mount), or to memory:// (with a warning) on a host where that directory is not usable. |
PAPERLESS_MCP_EVENT_STORE_URL |
(none) | Legacy state-backend override, used by build_event_store and build_kv_store only when kv_store_url is unset. It then backs every namespace, not just HTTP resumability. Prefer kv_store_url for new deployments. |
PAPERLESS_MCP_TASKS_URL |
(none) | Background-task (Docket) backend URL: memory:// is in-process and lost on restart; redis:// is durable and multi-process. When unset, a redis:// kv_store_url is reused for tasks too; otherwise fastmcp's memory:// default applies. Only applies when task-enabled tools exist. Applied via configure_task_backend. |
Background tasks¶
Every Paperless MCP instance wires a background-task backend at startup, so
a tool registered with task=True works with no extra setup.
PAPERLESS_MCP_TASKS_URL (under Persistence above) picks the backend:
memory:// runs tasks in-process and loses them on restart; redis://... is
durable and shared across processes. With neither it nor a redis:// KV
store set, the backend falls back to memory://, which the server logs at
startup when running over HTTP. The queue name comes from the
PAPERLESS_MCP prefix, so two servers sharing one Redis do not share a
queue.
Worker tuning stays on the native FASTMCP_DOCKET_* variables below. Set the
backend through PAPERLESS_MCP_TASKS_URL rather than
FASTMCP_DOCKET_URL: the former wins when both are set, and the server warns
about the disagreement.
| Variable | Default | Description |
|---|---|---|
FASTMCP_DOCKET_CONCURRENCY |
10 |
Maximum background tasks this worker runs at once. |
FASTMCP_DOCKET_WORKER_NAME |
(none) | Identifies this worker in the queue; defaults to a generated name. |
FASTMCP_DOCKET_REDELIVERY_TIMEOUT |
300 |
Seconds before a task claimed by a worker that never finished is redelivered to another. |
FASTMCP_DOCKET_RECONNECTION_DELAY |
5 |
Seconds to wait before reconnecting after the queue connection drops. |
FASTMCP_DOCKET_MINIMUM_CHECK_INTERVAL |
0.05 |
Seconds between queue polls; lower cuts latency and raises idle load. |
MCP Apps¶
| Variable | Default | Description |
|---|---|---|
PAPERLESS_MCP_APP_DOMAIN |
(none) | MCP Apps iframe domain, used for CSP sandboxing. Overrides the host derived from base_url. |
Logging¶
PAPERLESS_MCP_LOG_LEVEL sets how much every logger in the process says,
FastMCP's own included; -v on the command line forces DEBUG. The
unprefixed FASTMCP_LOG_LEVEL still works for one major version and logs a
deprecation warning that names the replacement.
PAPERLESS_MCP_LOG_FORMAT picks the renderer. rich writes one coloured
event key=value line per record, for a person at a terminal. json writes
one JSON object per record, with ts, level, logger and the event's own
fields as keys, for a log collector. Unset, the server chooses by itself:
rich when stderr is a terminal and json everywhere else, so a container
and a systemd unit log JSON with no configuration. Neither the image nor the
packaged unit sets anything.
The choice applies to the whole process. pvl-core owns the root logger and
switches FastMCP's own handlers off, so this server's paperless_mcp.*
lines and FastMCP's render through the same chain, as do uvicorn's. Access
lines from uvicorn.access are filtered rather than levelled: below DEBUG
only failed requests (status 400 and above) appear, and at every level the
query string is stripped and a credential in the path is redacted.
Set PAPERLESS_MCP_LOG_FORMAT=rich in .env or in
/etc/paperless-mcp/env to read a container's or a unit's log in
colour. A test runner is not a terminal either: a test that asserts on
Rich-shaped stderr needs the same setting, or it reads JSON.
| Variable | Default | Description |
|---|---|---|
PAPERLESS_MCP_LOG_LEVEL |
INFO |
Log level for every logger in the process, FastMCP's included (DEBUG / INFO / WARNING / ERROR / CRITICAL). The -v CLI flag overrides to DEBUG. The unprefixed FASTMCP_LOG_LEVEL still works for one major version and logs a deprecation warning. |
PAPERLESS_MCP_LOG_FORMAT |
(none) | Log rendering. rich is one colour event key=value line per record, for a terminal; json is one JSON object per record, for a collector. Unset picks rich when stderr is a terminal and json everywhere else, so a container or journald gets JSON with no configuration. |
Container runtime¶
Read by the container entrypoint (Docker / Compose), not by the server process.
| Variable | Default | Description |
|---|---|---|
PUID |
1000 |
Run the server process as this UID; the container entrypoint reassigns ownership of writable paths to match. |
PGID |
1000 |
Run the server process as this GID; pair with PUID to match the owner of a mounted volume. |
Remote debugger¶
Development only; the image must be built with --build-arg DEBUG=true, and
the protocol is unauthenticated. See
remote debugging.
| Variable | Default | Description |
|---|---|---|
PAPERLESS_MCP_DEBUG_PORT |
5678 |
debugpy listen port; the image must be built with --build-arg DEBUG=true. |
PAPERLESS_MCP_DEBUG_WAIT |
false |
Block startup until a debugger attaches. |
Domain variables¶
PAPERLESS_MCP_PAPERLESS_URL and PAPERLESS_MCP_API_TOKEN are the two
variables the server cannot start without: leave either unset and startup
stops with a message naming it. The table below still shows them under
Required: No, because that column reports whether the underlying field
declares a default rather than whether the server runs without a value; read
the description column for these two.
PAPERLESS_MCP_PAPERLESS_PUBLIC_URL
lets you name a different base URL for user-visible links than the internal API
URL the server calls; unset, it defaults to PAPERLESS_MCP_PAPERLESS_URL, and
trailing slashes are stripped from both.
A minimal .env:
PAPERLESS_MCP_PAPERLESS_URL=http://paperless.local:8000
PAPERLESS_MCP_API_TOKEN=abc123yourtokenhere
PAPERLESS_MCP_HTTP_TIMEOUT_SECONDS=60
PAPERLESS_MCP_DEFAULT_PAGE_SIZE=50
Document transfer links¶
Set PAPERLESS_MCP_BASE_URL to the public root URL of this MCP server and use
HTTP or SSE transport to enable document transfer links. A base URL of
https://mcp.example.com produces https://mcp.example.com/transfer/<token>.
Use the MCP server URL, not the Paperless URL, and omit the /mcp endpoint.
Your reverse proxy must route /transfer/ to the server. A path prefix in the
public URL requires the proxy to remove that prefix before forwarding.
The URL is a bearer capability: its recipient can transfer the file without MCP credentials. Give it only to the intended recipient. Existing inline interfaces remain available when no base URL is configured and under stdio.
The Transfer variables control lifetime, retry grace, reservation lease and upload size. File bytes stay out of MCP responses but are buffered in server memory; the upload cap does not limit download memory use.
Use one server process per transfer store. For restart persistence, configure
PAPERLESS_MCP_KV_STORE_URL with a persistent backend for tokens and upload
receipts. Concurrent replicas sharing that store cannot guarantee duplicate
prevention. To disable uploads, include create_document_upload_link alongside
other write tools in PAPERLESS_MCP_TOOLS_DENY, or use an allow list containing
only the tools you want. Previously issued links also respect these settings.
See file transfer links for downloads, Markdown uploads and task tracking.
Paperless¶
| Variable | Default | Required | Description |
|---|---|---|---|
PAPERLESS_MCP_PAPERLESS_URL |
(none) | No | Base URL of the Paperless-NGX REST API, without a trailing slash. The server refuses to start without it. |
PAPERLESS_MCP_API_TOKEN |
(none) | No | Paperless service-account token used for outbound API requests. The server refuses to start without it. |
PAPERLESS_MCP_HTTP_TIMEOUT_SECONDS |
30.0 |
No | Per-request HTTP timeout in seconds. |
PAPERLESS_MCP_HTTP_RETRIES |
2 |
No | Retries for idempotent requests after network errors or 5xx responses. |
PAPERLESS_MCP_DEFAULT_PAGE_SIZE |
25 |
No | Default page size for list tools, from 1 through 100. |
PAPERLESS_MCP_PAPERLESS_PUBLIC_URL |
(none) | No | Public Paperless UI URL for user-visible links; defaults to PAPERLESS_URL. |
Transfer¶
| Variable | Default | Required | Description |
|---|---|---|---|
PAPERLESS_MCP_TRANSFER_TTL_DEFAULT_S |
3600.0 |
No | Link lifetime in seconds when the caller requests no explicit TTL. |
PAPERLESS_MCP_TRANSFER_TTL_MAX_S |
86400.0 |
No | Ceiling in seconds a caller-requested link TTL is clamped to. |
PAPERLESS_MCP_TRANSFER_GRACE_TTL_S |
60.0 |
No | Post-success grace window in seconds: a served token's TTL shrinks to this so a stalled transfer can retry within it. |
PAPERLESS_MCP_TRANSFER_LEASE_S |
60.0 |
No | Crashed-handler reclaim window in seconds for an in-flight reservation. |
PAPERLESS_MCP_TRANSFER_MAX_UPLOAD_BYTES |
104857600 |
No | Maximum size in bytes of a single upload. |