Ceramic.ai is $0.25/1000 searches. I've been using it as an MCP in OpenCode and it seems adequate. I don't see many people talk about it, and I have not benchmarked it against Exa/Tavilly.
But it does seem like their index isn’t great.
coding agents is a very "niche" use-case where lexical matching works very well. code is a graph, by looking at few lines of code you can guess naming conventions etc. codebases are small compared to knowledge bases.
the bigger your index, the more you will need way better tools such as search.