GoCertius_MCP: Command for Claude Code

Evidence Lifecycle

Create and certify evidence in GoCertius. Evidence is always grouped: you create a group, add N evidences to it, then seal the group. Sealing is mandatory — an unsealed group stays in "capturing" state and is never certified.

Hierarchy

Case File
  └─ Evidence Group  (container; sealed once = certified)
       └─ Evidence   (one file per evidence item)

Required inputs

• case_file_id — UUID of the target case file (call session_info → case_file_list if unknown)
• use_case_id — UUID of the use case; reuse the one from an existing case file in the same account
• One or more files to certify: for each file you need its fileName, a human title, and the SHA-256 hash of the file content

Flow

1. Locate or create a case file

   • session_info → get userId
   • case_file_list with userId to find an existing case file
   • Or case_file_create if none exists (requires id UUID, name, description, useCaseId)

2. Create an evidence group

   • evidence_group_create with a generated UUID id, name, evidenceType: "FILE", and caseFileId
   • Note the group UUID — needed for every evidence and the final seal

3. Add evidence items (one call per file)

   Choose custody type based on who stores the file:

   EXTERNAL — you hold the file, GoCertius records the hash as proof of existence:

   • evidence_create with custodyType: "EXTERNAL", id, title, fileName, hash (SHA-256 hex, 64 chars), evidenceGroupId, caseFileId
   • The API may return a network error even when the evidence was persisted — verify with evidence_list if in doubt

   INTERNAL — GoCertius stores the file in S3, allowing the platform to verify the hash directly:

   • Easiest path — evidence_upload: pass the local file (filePath in stdio mode, or contentBase64) plus caseFileId, evidenceGroupId, title, fileName. It computes the SHA-256, registers the evidence, and uploads the bytes in one call — no manual hashing or PUT. Use this when the file is on the local machine.
   • Manual path — evidence_create with custodyType: "INTERNAL", same fields plus hash:
   • Response contains { uploadFileUrl, expiration } — a pre-signed S3 URL (valid ~10 min)
   • Upload the file: PUT <uploadFileUrl> with headers:
     • Content-Type: <mime-type>
     • x-amz-checksum-sha256: <sha256-base64> (SHA-256 of the file content, base64-encoded, not hex)
   • A 200 from S3 confirms the upload; GoCertius processes it asynchronously
   • Or pass fileUrl (public HTTPS, no redirect, <1 GiB) to evidence_create to have it download+upload automatically
   • Computing the base64 checksum: openssl dgst -sha256 -binary <file> | base64