--- markers) that describes the skill, and a Markdown body that contains the instructions or code. This page documents every field available in the frontmatter.
Required Fields
Every manifest must include these two fields:
Here is a minimal SKILL.md that only uses the required fields:
Optional Fields
These fields give you more control over how the skill behaves:Example with Optional Fields
Permissions
Thepermissions block declares resources a skill expects. The manifest parser
preserves these values, but the block is not a kernel permission boundary and
does not, by itself, grant or deny the daemon’s access. Enforce filesystem,
network, environment, and tool access through the relevant runtime controls.
Comis Namespace
Thecomis: block contains fields specific to the Comis platform. These control runtime requirements and platform-level behavior.
The
comis.requires fields are checked at startup using the runtime eligibility system. If a required binary or environment variable is missing, the skill is skipped with a warning — it does not crash the system. You can disable this check with skills.runtimeEligibility.enabled: false in your config, but that is not recommended.Input Schema
For skills that expect structured input, you can attach a JSON Schema in theinputSchema field. The schema is stored alongside the manifest and surfaced as documentation — agents can read it to understand what arguments the skill expects.
inputSchema is currently advisory: it documents the expected shape but is not enforced at invocation time. Treat it as a contract you and the agent agree to honor in the skill body, not a runtime guard.Complete Example
Here is a full SKILL.md using fields from every section:Template Substitution
Prompt skill bodies support placeholder syntax for dynamic content:- Named placeholders:
{placeholder}— mapped by name from the input parameters - Positional arguments:
$1,$2(1-indexed),$@or$ARGUMENTS(all arguments),${@:N}(arguments from position N onwards)
Prompt Skills
Step-by-step guide to creating your first prompt skill
Security Scanning
What Comis checks before loading your skill
Examples
Complete skill examples with walkthroughs
