Configuration¶
Everything starts with ossature.toml at the project root.
Minimal Config¶
[project]
name = "myproject"
version = "0.1.0"
spec_dir = "specs"
[output]
dir = "output"
language = "python"
[llm]
model = "anthropic:claude-sonnet-4-6"
The [llm] section with a model field is required. Everything else has defaults.
Project Section¶
[project]
name = "myproject"
version = "0.1.0"
spec_dir = "specs" # where .smd and .amd files live
context_dir = "context" # where user-provided context files live
Ossature discovers spec files automatically by scanning spec_dir recursively. You don't list them in the config.
Output Section¶
The language field tells the LLM what language to generate. It's not limited to a fixed list, but you'll get best results with common languages like python, typescript, rust, go, lua, etc.
Audit Section¶
Controls how many times the audit will attempt to fix errors in a spec and re-audit it. Each cycle sends the findings to the fixer LLM, applies edits, then re-audits the changed file. Defaults to 3.
Build Section¶
[build]
max_fix_attempts = 3 # verify-fail → fix → re-verify cycles per task
max_inline_lines = 200 # files above this aren't inlined in fix prompts
setup = "cargo init" # optional: run before the first task
verify = "cargo check" # optional: override default verification command
test = "cargo test" # optional: override default test command
The setup command runs once before the first build task. Useful for project initialization that the LLM shouldn't handle.
The verify and test commands override what Ossature uses to check generated code. If not set, the LLM determines verification commands per task based on the language and project structure.
The max_inline_lines field controls when files are inlined in fix prompts. When a task fails verification, Ossature sends the fixer LLM the error output and the current file contents. Files with more lines than this threshold are not inlined; the fixer uses its read_lines and grep_file tools to inspect them instead. This prevents blowing up the prompt on large files. Defaults to 200.
LLM Section¶
The model format is provider:model-name. Supported providers are anthropic and ollama.
The retries field controls how many times an agent retries when the model returns an invalid structured response (e.g., malformed JSON output). Defaults to 3.
The tool_retries field controls how many times a tool call can be retried when the LLM makes a mistake (e.g., edit_file with text that doesn't match the file). Defaults to 5. Increase for less capable or local models.
Set your API key as an environment variable:
Per-Role Overrides¶
You can use different models for different stages. This lets you use a stronger model for auditing and a faster one for fixing compilation errors.
[llm]
model = "anthropic:claude-sonnet-4-6" # default for all roles
audit = "anthropic:claude-opus-4-6" # spec review
planner = "anthropic:claude-sonnet-4-6" # plan generation
build = "anthropic:claude-sonnet-4-6" # code generation
fixer = "anthropic:claude-sonnet-4-6" # fixing failed tasks
brief = "anthropic:claude-sonnet-4-6" # brief generation
interface = "anthropic:claude-sonnet-4-6" # interface extraction
Any role that isn't explicitly set falls back to the default model.
Ollama (Local Models)¶
[llm]
model = "ollama:devstral-latest"
ollama_base_url = "http://localhost:11434/v1" # optional, this is the default
You can mix providers. Use Ollama for code generation and Anthropic for auditing:
[llm]
model = "ollama:devstral-latest"
audit = "anthropic:claude-opus-4-6"
planner = "anthropic:claude-sonnet-4-6"
fixer = "anthropic:claude-sonnet-4-6"
Config Discovery¶
Ossature searches for ossature.toml by walking up from the current directory. Override with --config:
Full Example¶
Here's a config for a Lua game project using context files:
[project]
name = "math_quest"
version = "0.1.0"
spec_dir = "specs"
context_dir = "context"
[output]
dir = "output"
language = "lua"
[llm]
model = "anthropic:claude-opus-4-6"
And one for a Python CLI tool with mixed models: