Tools & interfaces

GovBridge gives the model a tightly scoped, curated set of tools. There is no raw CMIS SQL pass-through and no arbitrary FIT-Connect API access: the model can only request these named operations (least privilege). Tool names are namespaced per protocol — cmis_* for DMS access, fit_* for FIT-Connect delivery. Which tools an endpoint offers depends on the provisioned protocol.

⚠️ The tool names themselves are German identifiers and stay that way in every language — they are part of the API contract, not display text.

CMIS — case files & documents

Read tools (always available)

Optional limit parameter on the searches: number of results, default 25, maximum 100.

Write tools (only when enabled)

These are only listed and executed if the endpoint has allow_writes = true. Otherwise they do not appear in tools/list at all and a direct call is rejected with a tool error.

Result formats

• Searches return a compact result list with name, base type, objectId and, where applicable, size — ideal so the model can continue working with the objectId.
• cmis_metadaten_lesen returns the object properties as formatted JSON.
• cmis_dokument_holen applies the size policy: text up to 32 KB inline as a resource, allowlisted binary types (PDF, DOC/X, XLS/X, PNG, JPEG) up to 5 MB as a base64 blob, anything larger or not listed only as a reference (cmis://<objectId>) with metadata — without the bytes.

FIT-Connect — application delivery

On an endpoint provisioned for the fit-connect protocol, the fit_* set is available instead of the cmis_* tools. It maps the sender flow of the FIT-Connect Submission API v2: applications are submitted end-to-end encrypted to a destination.

Read tool (always available)

Write tool (only when enabled + confirmed)

fit_antrag_senden is only listed if the endpoint has allow_writes = true, and on the SovrGPT side it additionally triggers the confirmation requirement (confirm_writes) — submitting an application is a deliberately gated, irrevocable action.

Further optional parameters: dataMimeType (default application/json), submissionSchemaUri (FIM or domain schema URI) and attachments (max. 10 attachments, each max. 5 MB, as filename + contentBase64 + mimeType).

How fit_antrag_senden proceeds

1. Check the destination and fetch the public encryption key (JWK).
2. announce — register the submission with the announced attachment IDs.
3. Upload the attachments — each attachment encrypted individually as a compact JWE.
4. finalize — transmit the encrypted metadata.json (with SHA-512 hashes) and the encrypted application data; the return value is the submissionId plus status.

Details on the mandatory encryption: Security & compliance.

CMIS 1.1 browser binding

Towards the backend, GovBridge speaks the CMIS 1.1 browser binding — a JSON-over-HTTP protocol of the OASIS standard CMIS. Specifically:

• Search via cmisselector=query with a CMIS SQL SELECT statement. The statement is assembled exclusively from escaped string literals — model text never reaches the query verbatim (injection protection).
• Metadata via cmisselector=object.
• Content via cmisselector=content (with a hard byte cap before buffering).
• Writing via cmisaction=createDocument or cmisaction=move (multipart form).
• The repository service document is resolved once per endpoint and cached briefly (5 min).

The backend API endpoint is freely configurable per endpoint (backend_base_url) — exactly the required behaviour: register the provided DMS API endpoint in the bridge and pull from it in real time.

FIT-Connect Submission API v2

For fit-connect endpoints, GovBridge speaks FITKO's Submission API v2. The backend_base_url points at the submission API instance; the service account (OAuth2 client credentials or basic) authenticates the bridge against the API. Characteristics:

• End-to-end encryption is mandatory. Application data, attachments and metadata.json are encrypted as compact JWE (RSA-OAEP-256 + A256GCM) with the destination's public key — the bridge decrypts nothing, and the backend only sees ciphertext.
• No compression (zip header), as required by v2.
• Integrity through SHA-512 hashes per content part, embedded in the contentStructure of the metadata.json.
• The flow is announce → attachment upload → finalize; the model only steers the domain fields, never the raw API calls.

Covered line-of-business systems

Because CMIS is an open standard, one adapter covers several DMS products — without a product-specific connector:

Each requires a reachable CMIS browser-binding endpoint with a service account (basic or OAuth2 client credentials).

MCP methods

Towards the SovrGPT client, GovBridge speaks the minimum necessary set of MCP methods: initialize (protocol negotiation 2025-06-18, fallback 2024-11-05), tools/list (filters write tools by allow_writes), tools/call and ping. More on the protocol: MCP server.

Next

• Setup — provision an endpoint.
• Security & compliance.