docs and pending

PENDING.md

@@ -33,7 +33,8 @@ FEATURES
   for getting governance parameters.
 
 * SDK
-    * [simulator] \#2682 MsgEditValidator now looks at the validator's max rate, thus it now succeeds a significant portion of the time
+  * [simulator] \#2682 MsgEditValidator now looks at the validator's max rate, thus it now succeeds a significant portion of the time
+  * [core] \#2775 Add deliverTx maximum block gas limit
 
 * Tendermint
 

docs/spec/baseapp/WIP_abci_application.md

@@ -0,0 +1,46 @@
+# ABCI application
+
+The `BaseApp` struct fulfills the tendermint-abci `Application` interface. 
+
+## Info
+
+## SetOption
+
+## Query
+
+## CheckTx
+
+## InitChain
+TODO pseudo code 
+
+During chain initialization InitChain runs the initialization logic directly on
+the CommitMultiStore and commits it. The deliver and check states are
+initialized with the ChainID. Additionally the Block gas meter is initialized
+with an infinite amount of gas to run any genesis transactions.
+
+Note that we do not `Commit` during `InitChain` however BeginBlock for block 1
+starts from this deliverState.
+
+
+## BeginBlock
+TODO complete description & pseudo code 
+
+The block gas meter is reset within BeginBlock for the deliver state. 
+If no maximum block gas is set within baseapp then an infinite 
+gas meter is set, otherwise a gas meter with the baseapp `maximumBlockGas` 
+is initialized 
+
+## DeliverTx
+TODO complete description & pseudo code 
+
+Before transaction logic is run, the `BlockGasMeter` is first checked for 
+remaining gas. If no gas remains, then `DeliverTx` immediately returns an error. 
+
+After the transaction has been processed the used gas is deducted from the
+BlockGasMeter. If the remaining gas exceeds the meter's limits, then DeliverTx
+returns an error and the transaction is not committed. 
+
+## EndBlock
+
+## Commit
+