molecule-core/docs/memory-plugins/pinecone-example

Pinecone-backed Memory Plugin (worked example)

A working sketch of a memory plugin that delegates storage to Pinecone instead of postgres.

This is example code, not a production binary. It demonstrates how to map the v1 contract onto a vector database. Operators who want to ship this would harden auth, add retries, batch the commit path, etc.

Why Pinecone is interesting

The default postgres plugin's pgvector index works for ~10M memories on a single node. Beyond that, semantic search becomes painful. A managed vector database can handle 1B+ memories, but the trade-offs are different:

• Capabilities: Pinecone is great at embedding (its core feature) but has no first-class FTS. So the plugin reports ["embedding"] and ignores the query field.
• TTL: Pinecone supports per-vector metadata with deletion via metadata filter — TTL becomes a periodic janitor task, not a per-row property.
• Cost: per-vector billing, so the plugin should batch writes and dedup before posting.

Wire mapping

Contract field	Pinecone shape
namespace	namespace (Pinecone's first-class concept)
id (caller-supplied)	id (Pinecone vector id; plugin upserts on this)
id (omitted)	Plugin generates uuid.NewString() before upsert
content	metadata.text
embedding	values
kind / source / pin / expires_at	metadata.{kind, source, pin, expires_at}
propagation (opaque JSON)	metadata.propagation (also opaque)

The contract's expires_at becomes a metadata field; a separate janitor cron periodically queries expires_at < now and deletes.

Pinecone's native upsert is the right fit for the idempotency-key contract: passing the same id twice updates in place. So a Pinecone plugin gets idempotent backfill retries "for free" if it just forwards MemoryWrite.id (or its generated UUID) to the upsert call.

Skeleton

package main

import (
    "context"
    "encoding/json"
    "log"
    "net/http"
    "os"

    "github.com/pinecone-io/go-pinecone/pinecone"
)

type pineconePlugin struct {
    client *pinecone.Client
    index  string
}

func main() {
    apiKey := os.Getenv("PINECONE_API_KEY")
    if apiKey == "" {
        log.Fatal("PINECONE_API_KEY required")
    }
    client, err := pinecone.NewClient(pinecone.NewClientParams{ApiKey: apiKey})
    if err != nil {
        log.Fatal(err)
    }
    p := &pineconePlugin{client: client, index: os.Getenv("PINECONE_INDEX")}

    http.HandleFunc("/v1/health", p.health)
    http.HandleFunc("/v1/search", p.search)
    // ... rest of the routes ...

    log.Fatal(http.ListenAndServe(":9100", nil))
}

func (p *pineconePlugin) health(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Content-Type", "application/json")
    json.NewEncoder(w).Encode(map[string]interface{}{
        "status":       "ok",
        "version":      "1.0.0",
        "capabilities": []string{"embedding"}, // no FTS, no TTL out-of-box
    })
}

func (p *pineconePlugin) search(w http.ResponseWriter, r *http.Request) {
    // Parse contract.SearchRequest
    // Build Pinecone QueryByVectorValuesRequest with body.Embedding
    // For each Pinecone namespace in body.Namespaces, call Query
    // Map results to contract.Memory
    // ...
}

What's missing from this sketch

A production-ready Pinecone plugin would add:

• Batch commits: bulk upsert N memories in a single Pinecone call
• TTL janitor: periodic deletion of expired vectors
• Connection pooling: keep one Pinecone client alive across requests
• Retry + circuit breaker: Pinecone occasionally returns 5xx
• Metrics: latency histograms per endpoint, write/read counters
• Idempotency-key handling: when MemoryWrite.id is supplied, forward it as the Pinecone vector id verbatim; otherwise generate one. Pinecone's Upsert is naturally idempotent on id match.

But the mapping above is the load-bearing part — the rest is operational hardening, not contract-specific.

See also

• Pinecone Go SDK docs
• Memory plugin contract spec
• Default postgres plugin source — for comparison