How do I set up a case logistics platform for dispatching mobile agents, capturing GPS proofs, and managing chain of custody?

To set up a case logistics platform for dispatching mobile agents, capturing GPS proofs, and managing chain of custody, design it around three core workflows:

1. Dispatch and assignment
2. Field proof collection
3. Chain-of-custody tracking

Here’s a practical blueprint.

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1) Define the workflow end to end

A typical case should move through these states:

• Case created
• Dispatched
• Accepted by agent
• En route
• Arrived at location
• Task performed
• Evidence/proof captured
• Transferred / handed over
• Completed / audited

Each state should generate an auditable event with:

• timestamp
• agent ID
• location
• device ID
• case ID
• optional signature/photo/notes

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2) Core platform modules

A. Case management

Store the case details:

• case ID
• customer / client
• priority
• SLA deadlines
• site/location
• required actions
• allowed agent qualifications
• required proof types
• custody rules

B. Dispatch engine

Automatically or manually assign agents based on:

• proximity
• availability
• certification/skills
• workload
• jurisdiction/region
• SLA urgency

Features to include:

• queue of available agents
• manual override
• reassignment with reason codes
• notifications via app/SMS/email
• acceptance/decline workflow

C. Mobile agent app

The field app should let agents:

• view assigned cases
• accept/decline jobs
• navigate to site
• check in/out
• capture GPS coordinates
• take photos/video/doc scans
• collect signatures
• add notes
• upload evidence offline and sync later

D. Proof capture

For GPS proofs, capture:

• latitude/longitude
• accuracy radius
• timestamp
• device time + server time
• map snapshot
• optional geofence validation
• optional photo with EXIF metadata

Useful proofs:

• arrival at geofence
• photo of site marker
• signed receipt
• scanned ID or document
• witness signature

E. Chain of custody module

This is critical for auditability. Track every handoff of case materials or evidence:

• who possessed it
• when they received it
• when they transferred it
• from whom to whom
• where the transfer occurred
• condition of item at transfer
• signatures and timestamps
• seal/box/barcode/QR ID

A custody event should be immutable once recorded.

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3) Data model you should implement

At minimum, these entities:

Case

• id
• status
• client_id
• assigned_agent_id
• priority
• location
• SLA_due_at
• metadata

Agent

• id
• name
• skill tags
• region
• current_status
• current_location
• device_id
• certification info

Assignment

• case_id
• agent_id
• assigned_at
• accepted_at
• declined_at
• reassigned_at
• dispatch_reason

Location proof

• case_id
• agent_id
• event_type (arrived, completed, etc.)
• gps_lat
• gps_lng
• accuracy_m
• timestamp
• photo_uri
• map_uri

Evidence item

• id
• case_id
• type
• barcode/qr_code
• description
• current_holder
• status

Custody event

• evidence_item_id
• from_user_id
• to_user_id
• event_type (handover, receipt, transfer, return)
• timestamp
• location
• signature_uri
• notes
• seal_condition

Audit log

• actor_id
• action
• entity_type
• entity_id
• timestamp
• before/after snapshot
• IP/device info

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4) GPS proof best practices

To make GPS evidence trustworthy:

• Capture server timestamp in addition to device timestamp
• Record GPS accuracy and reject low-quality fixes
• Use geofencing around destination
• Include photo proof with time/location metadata
• Log device ID and app version
• Detect spoofing/root/jailbreak where possible
• Store the original payload immutably
• Keep a full audit trail of edits and syncs

If legal/regulated use is involved, consider:

• digitally signing proof records
• hashing files
• storing hashes in tamper-evident storage
• retaining raw GPS source data

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5) Chain of custody rules

Implement these rules:

• Every item has one current custodian
• Transfers require both parties to acknowledge
• Each transfer creates a non-editable event
• Evidence condition is recorded at each handoff
• Attach signatures, photos, or barcode scans
• Any break in custody must be explicitly marked
• Make the history exportable for audit/legal review

If you handle physical assets:

• use QR/barcode labels
• seal numbers
• package IDs
• scan at every handoff

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6) Dispatch logic

A basic matching algorithm can score agents by:

• distance to site
• skill match
• availability
• priority level
• historical performance
• SLA feasibility

Example:

• 40% proximity
• 25% skill fit
• 20% availability
• 15% SLA urgency

Then assign the highest-scoring eligible agent.

Also add:

• timeout if agent doesn’t accept
• auto-escalation to supervisor
• fallback pool of agents
• shift-based assignment windows

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7) Suggested architecture

Frontend

• Web portal for operations/admin
• Mobile app for field agents

Backend services

• Auth/identity service
• Case service
• Dispatch service
• Proof/evidence service
• Custody/audit service
• Notification service

Storage

• Relational DB for core records
• Object storage for images, signatures, docs
• Event log / append-only store for audits

Integrations

• Maps/geocoding
• SMS/push notifications
• Identity/SSO
• Barcode/QR scanning
• E-signature provider if needed

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8) Security and compliance

Because this involves field operations and evidence, build for:

• role-based access control
• MFA for admins/supervisors
• encryption at rest and in transit
• immutable audit logs
• least privilege access
• offline sync conflict handling
• retention policies
• consent/privacy controls for location tracking

If applicable, confirm requirements for:

• labor/privacy laws
• evidence handling standards
• jurisdictional data retention
• regulatory or court admissibility rules

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9) Operational dashboards

Useful dashboards:

• open cases by status
• agent utilization
• SLA breaches
• proof completion rate
• geofence arrival compliance
• custody exceptions
• failed syncs / offline uploads
• evidence transfer history

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10) MVP scope

If you want a first version quickly, build:

1. Case creation and assignment
2. Mobile check-in with GPS capture
3. Photo/signature upload
4. Basic custody transfer logging
5. Audit log
6. Admin dashboard

Then add:

• geofencing
• barcode/QR scan custody
• automated dispatch scoring
• offline mode
• tamper detection
• advanced reporting

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11) Recommended implementation sequence

1. Define case statuses and custody events
2. Build agent app with location proof capture
3. Build backend APIs and audit logging
4. Add dispatch rules and notifications
5. Add evidence item tracking and transfers
6. Add reporting and exception handling
7. Harden security, immutability, and compliance controls

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If you want, I can also provide:

• a database schema
• API endpoint list
• mobile app screen flow
• or a reference architecture diagram in text form