Cost
Request/session cost facts, pricing basis where available, and the reason a budget decision allowed or denied work.
Cross-cutting proof layer
Talon can prove how the control plane behaved.
Evidence is not the product category. It is the receipt under operation: which AI use case called, what policy decided, what cost or session fact applied, which provider path was attempted, what PII or tool facts were observed, and whether the stored record still verifies.
talon audit list
talon audit show req_a1b2c3d4
talon audit verify req_a1b2c3d4
✓ Evidence signature VALID
# HMAC-signed = tamper-evident
# not magically immutableCost decisionsReliability pathPolicy reasonsSession historyPII/tool factsDestinationSignature
Evidence under the four pillars
Runtime proof should explain operation, not replace it.
Reliability
Linked provider fallback attempts and the terminal selected or fail-closed outcome on supported paths.
Policy and sessions
Decision reasons, PII/tool context, provider/model path and asserted-session correlation where present.
Session evidence
Review a multi-request run as one unit.
For asserted sessions, Talon can list, export, cost and verify the requests that share the session identity across supported provider routes. The evidence supports operator explanation without inventing grouping for synthetic request IDs.
talon audit list --session <id>
talon audit export --session <id>
talon audit verify --session <id>
talon costs --session <id> --json
# asserted session → real session view
# synthetic request ID → correlation onlyReliability evidence
Show that recovery did not bypass policy.
When supported transient failure engages a fallback chain, Talon can record failed attempts, policy-valid candidate handling and the terminal outcome. A successful response is not the whole story; the attempted path matters.
primary → timeout
→ signed attempt fact
fallback candidate
→ policy re-check
→ selected OR skipped
terminal outcome
→ fallback served OR fail closedData and scanner evidence
Know which detection path informed the decision.
On supported scanner paths, evidence can preserve PII findings, scanner identity and typed failures instead of silently pretending a scan succeeded. This is useful proof under shared policy, not a standalone product category.
scanner facts can include:
- scanner type / engine
- version
- duration
- typed failure
- PII findings
# enforcement-path scanner failure can fail closedTool and action boundary
Evidence is only as complete as the intercepted path.
Talon can record tool schemas visible to gateway traffic and MCP/tool calls routed through its interception path. Local shell commands, file edits, browser actions and direct APIs that bypass Talon are not controlled or evidenced by Talon.
intercepted path
→ decision + runtime fact
→ signed record
bypass path
→ no Talon decision
→ no Talon evidenceReview workflow
Inspect, export, sample and verify.
| Review need | Command or artifact | What it supports |
|---|---|---|
| Explain one decision | talon audit show <id> | Policy, data, provider, cost and reason context where recorded. |
| Review one asserted session | talon audit list --session <id> | Session-scoped history and outcomes. |
| Verify integrity | talon audit verify <id> | The stored record still matches its HMAC signature. |
| Hand off evidence | talon audit export | CSV/JSON artifacts for technical review and audit support. |
| Explain sovereignty posture | talon compliance sovereignty --format html | Configured controls plus observed destination facts where available. |
Do not take the receipt on trust
Create a record, change a signed field and verify the failure.
The evidence demo is useful because it tests the integrity claim directly. A valid HMAC shows the record has not changed since Talon signed it; it does not turn SQLite into an immutable ledger.