Question: I'm looking for a tool that helps me develop believable characters and dialogue for my novel.

If you want a single tool to help you craft believable characters and dialogue for your novel, Novelcrafter is worth a look. This novel writing suite includes a personal Wiki (Codex) to store and organize story details, multiple writing modes, and AI tools to help you write from start to finish. The Codex is a central repository for characters, locations, objects, lore and other elements, so you can easily track them as they appear in different scenes and books.

Another tool that can help you build your narrative structure and consistency is Subtxt, which uses AI to help you construct your story. It includes tools like Narrative Agents, Subtxt Muse, Premise Builder and Storyteller's Lexicon, so it's a powerful framework for your story. Subtxt can help you identify gaps in your narrative and generate content to fill them in, which means your story will be more coherent and compelling.

StoryNest.ai is another option. This AI-based tool offers a variety of tools for crafting compelling stories, novels and interactive stories. Among its features are character creation, world-building, AI-assisted editing and proofreading, which can help you refine your writing and flesh out your story. You can also integrate with other writers and AI tools, so it's a flexible and active writing companion.

If you're struggling with writer's block, Sudowrite is worth a look. It uses AI to help you generate ideas, create outlines, write drafts, edit and refine your work. With tools like Describe, Story Bible, Write and Expand, Sudowrite can help you create character descriptions, plot out stories and refine your writing style. It's designed to help you be more creative and productive while making the writing process more enjoyable.