docs: add cost estimator docs (#513)

* docs: add cost estimator docs

* docs: fix typo

* docs: improve readability of commands

Author: fakedev9999

book/SUMMARY.md

@@ -40,6 +40,7 @@
     - [Celestia DA](./fault_proofs/experimental/celestia.md)
 
 - [Advanced](./advanced/intro.md)
+  - [Cost Estimator](./advanced/cost-estimator.md)
   - [Reproduce Binaries](./advanced/verify-binaries.md)
   - [Node Setup](./advanced/node-setup.md)
   - [Kurtosis](./advanced/kurtosis.md)

book/advanced/cost-estimator.md

@@ -0,0 +1,54 @@
+# Cost Estimator
+
+The Cost Estimator is a powerful tool that allows you to estimate proving costs for op-succinct without actually generating proofs. This helps you **optimize your proof generation strategy** by identifying potential causes of unexpected costs.
+
+## Overview
+
+The cost estimator simulates the proof generation process and provides detailed metrics including:
+- Total instruction count
+- Oracle verification costs
+- Derivation costs
+- Block execution costs
+- Blob verification costs
+- **SP1 gas usage**
+- Transaction counts and EVM gas usage
+- Various precompile cycles (BN pair, add, mul, KZG eval, etc.)
+
+## Setup
+
+Before running the cost estimator, you need to set up a .env file in the project root directory with the following RPC endpoints:
+
+```bash
+L1_RPC=<YOUR_L1_RPC_ENDPOINT>
+L1_BEACON_RPC=<YOUR_L1_BEACON_RPC_ENDPOINT>
+L2_RPC=<YOUR_L2_RPC_ENDPOINT>
+L2_NODE_RPC=<YOUR_L2_NODE_RPC_ENDPOINT>
+```
+
+## Usage
+
+To run the cost estimator, use the following command:
+
+```bash
+RUST_LOG=info cargo run --bin cost-estimator -- \
+    --start <START_BLOCK> \
+    --end <END_BLOCK> \
+    --batch-size <BATCH_SIZE>
+```
+
+Example:
+
+```bash
+RUST_LOG=info cargo run --bin cost-estimator -- \
+    --start 2000000 \
+    --end 2001800 \
+    --batch-size 1800
+```
+
+<br>
+
+For the best estimation, use a range bigger than the batcher interval with the batch size equal to the range.
+
+### Output
+
+The execution report is saved in the `execution-reports/{chain_id}/{start_block}-{end_block}-report.csv` directory.