Configuration

Configuration options

Pass a dexcost.Config struct to dexcost.Init(). Init is safe to call multiple times — only the first call takes effect.

Init returns an error if the API key format is invalid, the buffer directory cannot be created, or the pricing engine fails to load.

err := dexcost.Init(dexcost.Config{
    APIKey:               "dx_live_...",
    BatchSize:            200,
    FlushIntervalSeconds: 10.0,
    RedactFields:         []string{"prompt", "completion"},
    HashCustomerID:       true,
    TrackHTTP:            true,
    EnableRetryHeuristics: true,
})
if err != nil {
    log.Fatalf("dexcost init: %v", err)
}
defer dexcost.Close()

Environment variables

Environment variables are read inside Config.init() when Init is called. Explicit field values in Config take precedence over environment variables.

Development mode

Pass Environment: "development" in Config (or set DEXCOST_ENV=development) to enable dev mode:

dexcost.Init(dexcost.Config{Environment: "development"})

In dev mode:

• Every llm_call, external_cost, compute_cost, and retry_marker event is printed to stderr as it is recorded, with provider, model, token counts, and cost.
• Task completion is printed with aggregated cost totals and retry counts.
• Cloud push is disabled — the SyncWorker (EventPusher) is not started.
• An API key is not required.

Dev mode is controlled by the module-level devMode variable, managed by dexcost.EnableDevMode() and reset by dexcost.Close(). dexcost.IsDevMode() returns the current state.

Attribution & context

SetContext and SetContextWithMetadata

dexcost.SetContext attaches customer_id and project_id to a context.Context without starting an explicit task. HTTP adapters and wrapper clients use this attribution when no explicit task is present:

ctx = dexcost.SetContext(ctx, "acme-corp", "chatbot-v2")
resp, err := trackedClient.CreateChatCompletion(ctx, req)

dexcost.SetContextWithMetadata additionally sets an agent name and arbitrary metadata:

ctx = dexcost.SetContextWithMetadata(ctx,
    "acme-corp",      // customerID
    "chatbot-v2",     // projectID
    "support_agent",  // agent name
    map[string]interface{}{
        "tier":   "enterprise",
        "region": "us-east-1",
    },
)

Both functions return a derived context.Context and follow standard Go context propagation — pass the returned context to all downstream calls.

dexcost.GetContext(ctx) returns the *core.ContextData stored in the context, or nil. dexcost.ClearContext(ctx) returns a context with attribution removed.

WithCustomer and WithProject

dexcost.WithCustomer and dexcost.WithProject are TaskOption values that set attribution on a specific task at StartTask time:

ctx, task := dexcost.StartTask(ctx, "resolve_ticket",
    dexcost.WithCustomer("acme-corp"),
    dexcost.WithProject("support"),
)

Additional task options: dexcost.WithMetadata(map[string]interface{}{...}), dexcost.WithExperiment("exp-id"), dexcost.WithVariant("variant-a").

CLI

The dexcost CLI works offline against the local SQLite buffer. No API key is required.

Install via go install:

go install github.com/DexwoxBusiness/dexcost-go/cmd/dexcost@latest

dexcost status

Show the state of the local buffer:

dexcost status
dexcost status --db /path/to/dexcost.db

Output includes: DB location, event count, task count, last task timestamp, pending and synced event counts, and the current pricing data version.

dexcost rates

Manage the per-service cost rate registry. Rates are stored persistently at ~/.dexcost/rates.yaml:

# List all registered rates
dexcost rates --list

# Import rates from a YAML file into the persistent store
dexcost rates --import rates.yaml

# Export the persistent store to a YAML file
dexcost rates --export rates.yaml

# Override the default store location
dexcost rates --store /path/to/rates.yaml --list

YAML format expected by --import (canonical format shared with the Python SDK):

rates:
  maps.googleapis.com:
    per: request
    cost_usd: "0.005"
  ocr-api.com:
    per: page
    cost_usd: "0.01"

dexcost scan

Static-analysis scan of your codebase to find cost points that are not yet tracked. No API key or network connection is required:

dexcost scan ./cmd
dexcost scan ./cmd --generate-stubs

scan walks the target directory (default .), identifies LLM call sites (reported as auto-instrumented), and flags external API calls that likely incur cost but have no RecordCost() call nearby (reported as needing manual recording).

--generate-stubs prints ready-to-paste RecordCost() snippets for each untracked cost point found.