#Enrichers

Enrichers dynamically modify MCP tool schemas and transform arguments at runtime. They implement the ToolEnricher trait from devboy-core.

#How It Works

tools/list request
    ↓
Executor collects base tool schemas
    ↓
Each enricher modifies schemas:
  - Remove unsupported params (GitHub: no priority)
  - Add enum values from metadata (ClickUp: status list)
  - Replace customFields with typed cf_* params (Jira)
    ↓
Return enriched schemas to client

tools/call request
    ↓
Each enricher transforms args:
  - cf_story_points: 5 → customFields: { "customfield_10001": 5 }
  - priority: "urgent" → priority: 1 (ClickUp numeric)
    ↓
Provider receives normalized args

#ToolEnricher Trait

pub trait ToolEnricher: Send + Sync {
    /// Which tools this enricher applies to.
    fn supported_tools(&self) -> &[&str];

    /// Modify schema during tools/list.
    fn enrich_schema(&self, tool_name: &str, schema: &mut ToolSchema);

    /// Transform args before execution.
    fn transform_args(&self, tool_name: &str, args: &mut Value);
}

#Built-in Enrichers

#Static Enrichers (no metadata needed)

GitLabSchemaEnricher — removes params not supported by GitLab:

• Removes: priority, parentId, customFields, issueType, components, projectId, points
• Adds: link_type enum ["relates_to", "blocks", "is_blocked_by"]

GitHubSchemaEnricher — removes params not supported by GitHub:

• Same removals as GitLab
• link_issues tool marked as unsupported
• transform_args: maps line_type → GitHub side parameter (old→LEFT, new→RIGHT)

#Dynamic Enrichers (require metadata)

ClickUpSchemaEnricher — adapts tools using list metadata:

• Adds status enum from list statuses
• Adds priority enum ["urgent", "high", "normal", "low"]
• Replaces customFields with individual cf_* params from custom field definitions
• transform_args: maps cf_* back to ClickUp format (dropdown name→orderindex, labels name→id)
• transform_args: maps priority name→numeric (urgent→1, high→2, normal→3, low→4)

JiraSchemaEnricher — adapts tools using project metadata:

• Adds issueType enum from project issue types (excludes subtask types)
• Adds priority enum from project priorities with alias hints
• Adds components enum from project components
• Single project: removes projectId, replaces customFields with cf_*
• Multi-project: projectId becomes enum of project keys, keeps generic customFields
• transform_args: maps priority aliases (urgent→Highest, high→High, etc.)
• transform_args: maps cf_* to Jira format (option name→{id}, array names→[{id}])

#Pipeline Enrichers

PipelineFormatEnricher — adds format parameter to list tools:

• Adds format enum ["markdown", "compact", "json"] to read tools
• Default: markdown

#Custom Fields

ClickUp and Jira support custom fields with different value transformation semantics:

#ClickUp Field Types

#Jira Field Types

#Creating a Custom Enricher

use devboy_core::{ToolEnricher, ToolSchema};
use serde_json::Value;

pub struct MyEnricher {
    allowed_statuses: Vec<String>,
}

impl ToolEnricher for MyEnricher {
    fn supported_tools(&self) -> &[&str] {
        &["get_issues", "create_issue"]
    }

    fn enrich_schema(&self, _tool: &str, schema: &mut ToolSchema) {
        schema.set_enum("status", &self.allowed_statuses);
    }

    fn transform_args(&self, _tool: &str, _args: &mut Value) {
        // No transformation needed
    }
}

Register with the executor:

executor.add_enricher(Box::new(MyEnricher {
    allowed_statuses: vec!["open".into(), "closed".into()],
}));