# Capability Source Matrix

Date: 2026-07-09
Stage: C log-backed receive implementation
Evidence index: `docs/source-discovery/2026-07-09-n12-pre-zyl-index.md`
Schema notes: `docs/source-discovery/2026-07-09-n12-pre-zyl-schema-notes.md`

## Source priority

1. Existing bridge / API / local service.
2. Local data, log, cache, or database source.
3. UIA helper source through C# WinHelper.
4. Network/protocol source.
5. Mock source for tests only.

## Matrix

| MCP tool | Primary source | Fallback source | Evidence file | Decision status | Next implementation slice |
| --- | --- | --- | --- | --- | --- |
| `isphere_receive_messages` | decrypted `PacketReader.ProcessPacket` XMPP `<message>` stanzas via `internal/isphere.EncryptedPacketLogSource` | decrypted `Smark.SendReceive` transport stanzas; decrypted `SaveToDB` `Chat_OnMessageArrived` traces; wrapped `MsgLib.db` after DB wrapper is solved | `docs/source-discovery/2026-07-09-n12-pre-zyl-schema-notes.md#field-mapping-evidence` | C5 env loader wired through ISPHERE_PACKET_LOG_FILE; default source remains empty when unset | fixture-backed configured-source operator smoke |
| `isphere_search_contacts` | bare sender/receiver JIDs extracted from normalized log-backed messages | decrypted roster/contact stanzas from `Smark.SendReceive`; `MsgLib.db` contact/conversation tables after DB wrapper is solved; UIA helper source if display names are missing | `docs/source-discovery/2026-07-09-n12-pre-zyl-schema-notes.md#log-decryption-result` | C8 MCP tool registered and verify-go-mcp covers default/configured contact smoke; JID-only display/account fallback | enrich display names from roster/db/uia evidence |
| `isphere_search_groups` | decrypted `PacketReader.ProcessPacket` `type="groupchat"` stanzas and conference/MUC JIDs | `MsgLib.db` group/conversation tables after DB wrapper is solved; UIA helper source if group display names are missing | C9 ignored-log scan: PacketReader 86 groupchat/86 conference hits; Smark 24 groupchat/658 conference/631 muc hits | C11 MCP tool registered and verify-go-mcp covers default/configured group smoke; JID-only display fallback | enrich group display/member data from roster/db/uia evidence |
| `isphere_receive_files` | decrypted `PacketReader.ProcessPacket` file-transfer message stanzas plus `zyl\importal\<hash>` cache mapping | decrypted `Smark.SendReceive` and `SaveToDB` traces for file-reference reconciliation | `docs/source-discovery/2026-07-09-n12-pre-zyl-schema-notes.md#field-mapping-evidence` | candidate pending cache-reference mapping | fourth |

## Stage C entry rule

Open implementation only for the selected row whose evidence maps concrete fields to the MCP output contract. After Stage B2, `isphere_receive_messages` satisfies the entry rule through decrypted `PacketReader.ProcessPacket` XML shape.

## Stage C first slice recommendation

Start Stage C with a narrow log-backed `isphere_receive_messages` source abstraction:

1. Implement DES/CBC/PKCS7 line decryption for `IMPP.Util.Log.LogSecurityPolicy` format.
2. Implement a parser for decrypted `PacketReader.ProcessPacket` XMPP `<message>` stanzas.
3. Normalize only redacted test fixtures into message structs first.
4. Add the MCP tool registration after the parser/source abstraction passes tests.

## Deferred source work

`MsgLib.db` is deferred because the selected DB files are not direct SQLite and did not decrypt to a SQLite header with the known log policy key. A separate DB-wrapper analysis node is required before using DB tables as a production read source.