It's possible to use create an MCP installation for versions of Minecraft where there hasn't been a full MCP release. It takes a little bit of manual setup, but the end result is highly useful.

1. Download and extract the most recent MCP build from http://www.modcoderpack.com/website/releases.

2. Edit version.cfg in the conf folder, and change ClientVersion and ServerVersion to the version you want (for instance, 1.10.2).

3. Download the SRG zip for the version you want; these can generally be found at http://mcpbot.bspk.rs/mcp/<version>/mcp-<version>-srg.zip (for example, http://mcpbot.bspk.rs/mcp/1.10.2/mcp-1.10.2-srg.zip).

4. Extract that zip into the MCP conf folder, overwriting files and the contents of the patches folder.

5. Download the latest daily mappings from http://export.mcpbot.bspk.rs/. Even if they aren't for exactly the version you want, they will generally work.

6. Extract the mapping zip into the MCP conf folder, overwriting files.

7. Run MCP's decompile.bat as you normally would.

Note that for this to work, there must be a released SRG file for the version you want. The SRG file is what converts obfuscated names into an intermediate step where names are (mostly) the same between versions; the mappings files convert those intermediate names into the names you see and are used to.