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+# AID list (`aidlist.json`)
+<a id="top"></a>
+
+This file acts as a database of ISO/IEC 7816 application identifiers (AIDs) and their human-readable metadata.
+
+It is used by commands that try known app selections and then print decoded information (for example `hf 14a info --aidsearch`, `hf 14b info --aidsearch`, etc.).
+
+## Format
+Each entry in `client/resources/aidlist.json` must contain all of the fields below (use an empty string if data is unknown):
+
+- `AID`: Application Identifier as a hex string, no spaces or separators, representing raw bytes in ISO7816 select order (big-endian byte order as transmitted in APDU data).
+- `Vendor`: Organization, scheme, ecosystem owner, or issuer most directly associated with this AID. Specify multiple issuers with a comma or semicolon separator.
+- `Country`: Primary country associated with the vendor or deployment context. Leave empty when unknown or globally used.
+- `Name`: Short user-facing application name.
+- `Description`: Extra context, disambiguation, references, legacy naming, known usage notes, or deployment-specific remarks.
+- `Type`: High-level category tag (for example `transport`, `emv`, `gp`, `pacs`, `ndef`).
+
+Example:
+```json
+{
+    "AID": "A00000039656434103F1216000000000",
+    "Vendor": "LV Monorail",
+    "Country": "United States",
+    "Name": "Las Vegas Monorail",
+    "Description": "Used on Las Vegas Monorail during Google Wallet Mifare 2GO demo period",
+    "Type": "transport"
+}
+```