Instructions Sysvar
Programming Model · Abyss
A special sysvar account (address: Sysvar1nstructions1111111111111111111111111) that provides on-chain programs read access to all instructions in the current transaction. Unlike other sysvars, it cannot be read via sol_get_sysvar and must be explicitly included as an account in the instruction. Programs use it for instruction introspection: verifying co-occurrence of precompile signature verifications (Ed25519/Secp256k1), detecting CPI context (distinguishing top-level calls from nested CPI), and enforcing instruction ordering constraints.