nifty way to find file format

Here's something I found on the internet. If you wanted know the file format and there is little or no documentation of the proprietary format, you can look up the header of the file  and other data structures with the corresponding symbols from kernel PDB file. You don't need the source to look up format.
There are tools that can render the information in the PDB to be navigated through the UI. This is possible via the DIA SDKs. The format of PDB files is also not open hence their access is via debugger sdk. The SDK is available via COM. So you may have to register the DIA dll.
The debuggers make a local cache of the symbols when requested and they download the symbols from the symbol server, so you can expect the PDB to be made available to you by the debugger in the directory you specify.
If you look at the kernel PDB, you will find the structures we are looking for, start with the name MINIDUMP and these can be walked from the header onwards.
To find the stack trace, we follow the header to the directory or stream for the exception and read the exception record and address where the exception occurred. Both of these are given in the MINIDUMP_EXCEPTION data structure. The exception stream also gives the thread context. The context gives the processor specific register data. When we dump the stack pointer, we get the stack trace. We resolve the symbols of the stack trace with the pdbs either explicitly through DIA or implicitly through the managed mdbgeng library of debugger sdk. The minidump actually has all the information in the file itself. For example, you can list all the loaded modules with the mindump module list as well as the mindump module structures. Module name, function name, line number and stack frame are available via IMAGEHLP data structures. The various types of streams in the minidump are :
Thread list stream given by the MINIDUMP_THREAD_LIST structure
Module list stream given by the MINIDUMP_MODULE_LIST structure
Memory list stream given by the MINIDUMP_MEMORY_LIST structure
Exception stream given by the MINIDUMP_EXCEPTION_STREAM structure
System Info stream given by the MINIDUMP_SYSTEM_INFO structure
ThreadExList stream given by the MINIDUMP_THREAD_EX_LIST structure
Memory64 list stream given by the MINIDUMP_MEMORY64_LIST structure
Comment stream
Handle Data stream given by the MINIDUMP_HANDLE_DATA_STREAM structure
Function table stream given by the MINIDUMP_FUNCTION_TABLE structure
Unloaded module list stream given by the MINIDUMP_UNLOADED_MODULE_LIST structure
Misc Info List stream given by the MINIDUMP_MISC_INFO structure
Thread Info List stream given by the MINIDUMP_THREAD_INFO_LIST structure
Handle operation  list stream given by the MINIDUMP_HANDLE_OPERATION_LIST structure
For diagnostics, we may choose to display messages to the output or error stream. More features can be built into the tool that retrieves the stack trace from the dump. This can be done in an extensible manner where tool runs a set of commands from the user by way of command line. Internally we can have a command pattern to implement the different debugger like functionalities of the tool. Also the tool can be deployed via MSI. This ensures cleanliness during install and uninstall.