Head to head · Memory search · October 2026 research run

Context Mode Engine vs Agent Platform Memory Bank

Agent Platform Memory Bank scores 65.6 (B) on agent readiness against Context Mode Engine's 54.6 (C), and leads in 5 of 7 scored categories. Context Mode Engine leads on agent ergonomics and payments & pricing. Both do memory search.

Best memory layers for AI agents · All 353 memory comparisons

Which one, for what

Context Mode Engine C

Best for Coding-agent users who want large tool output kept out of the context window on their own machine.

Ahead on

  • Agent ergonomics, 80 against 75
  • Payments & pricing, 40 against 20

Also in its favour

  • No key needed to call it
  • Runs on your own machine

Watch for

Elastic License 2.0, not an OSI licence, with hosted-service restrictions

Agent Platform Memory Bank B

Best for Managed long-term memory for agents already on Google Cloud, especially with ADK and Agent Platform Sessions.

Ahead on

  • Reliability, 68 against 60
  • Schema & documentation, 75 against 67
  • Security & auth, 72 against 35
  • Maintenance & community, 62 against 55
  • Transparency & trust, 81 against 54

Also in its favour

  • A hosted endpoint, with nothing to install

Watch for

Needs a Google Cloud project with billing, set up by a person in the console

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Security & auth Agent Platform Memory Bank +37

Context Mode Engine 35

Read with the framework lines for a local MCP server. No credential of its own; code runs as the user under the agent's own permission checks (10). On Claude Code the PreToolUse hook applies the user's deny rules first, and CONTEXT_MODE_REQUIRE_SECURITY=1 denies every call while a settings file is broken (15). ctx_index blocks private and link-local addresses when it fetches a URL, but no guidance on instructions inside fetched pages or tool output (0). Each project keeps a local session log of prompts, edits, commands and errors (10). No SECURITY.md, security.txt or disclosure route found, and no advisory names the package (0). 10+15+0+10+0 = 35.

Agent Platform Memory Bank 72

OAuth 2.0 with IAM and service accounts (30), less 10, as for the other Google API listings, because the v1 discovery document lists access_token, oauth_token and key as query parameters (20 of 30). IAM Conditions can restrict access by memory scope; purge and delete have no confirmation (15 of 20). Memories are written by an LLM from conversation content and returned to agents, with no injection guidance found (5 of 15). Access Transparency and Access Approval are listed; Cloud Audit Logs coverage for Memory Bank wasn't read (12 of 15). Google's valid security.txt, vulnerability reward programme and certifications, with HIPAA listed for Memory Bank (20). Total 72.

Transparency & trust Agent Platform Memory Bank +27

Context Mode Engine 54

Elastic License 2.0, source available but not an OSI licence, with limits on offering it as a hosted service (15). The Engine privacy page says data stays in ~/.context-mode, gives retention (indexed items go after 30 days unread, 500 MB per project, idle projects after 14 days) and deletion by ctx_purge. The site privacy page is a summary for the Gateway that points to e-mail for the full policy (25 of 30). No deprecation policy or dated notices (0). The README and docs state zero telemetry and list each network call, with a source test that flags new call sites. We found no telemetry in the source (20). 15+25+0+20 = 60.

Agent Platform Memory Bank 81

Closed service under the Google Cloud terms (15). Data residency at rest, CMEK and the Cloud Data Processing Addendum apply; no Memory Bank retention period or time-to-live was read (20 of 30). The rename was announced in the release notes with old and new names listed, and Google's deprecation policy covers GA services (14 of 20). Google Cloud's subprocessor list and regional endpoints are published (16 of 20). Total 65.

Payments & pricing Context Mode Engine +20

Context Mode Engine 40

No machine payment protocol found (0). Scored on the hosted Gateway, the paid option. Extra requests cost $2.00 down to $1.00 per 1,000 by volume, published on the pricing page (20). A free plan of 1,000 requests every month, no card (20). A person signs in to the console with GitHub or Google (0). 0+20+20+0 = 40.

Agent Platform Memory Bank 20

No x402, MPP or L402 (0). Storage, read and write prices are published without a login (20). No Memory Bank free tier found (0). A person creates the project, enables billing and sets up IAM in the console (0). Total 20.

Reliability Agent Platform Memory Bank +8

Context Mode Engine 60

Read with the local-package lines. Installs from npm as context-mode, with Node 24.15.0 or later stated in package.json and the README (20). A public CI workflow runs the test gate on macOS, Linux and Windows under Node 24.15.0 and 26 on every push, and the release workflow runs it before each publish. GitHub's pages answer 403 in this session, so run results couldn't be read (15 of 25). Open crash and regression issues weren't read (0). Versioned releases, with 2.0.0 a major for the rewrite and 2.0.0-next prereleases from 27 October, but no changelog file in the repository and the GitHub release notes unread (10 of 15). Version 2.1.0, past 1.0 (15). 20+15+0+10+15 = 60.

Agent Platform Memory Bank 68

Hosted lines. Google Cloud status dashboard with per-product history (20). Its incident feed, read on 6 November 2026, holds four incidents since 8 August (20 August, 27 products; 1 September, us-central1-b; 8 October, Cloud Storage; 20 October, europe-west2, 38 products), and none names Agent Platform, Vertex or Memory Bank (30). No Memory Bank quotas or rate limits were found; the platform quotas path guessed returned 404 (0, unchecked). Generation is a long-running operation with wait and cancel methods, and Google's retry guidance wasn't re-read for this API (8 of 15). No SLA for Memory Bank was found in the pages read (0, unchecked). Memory profiles, IngestEvents and multi-regional endpoints are GA (10). Total 68.

Schema & documentation Agent Platform Memory Bank +8

Context Mode Engine 67

No published contract. The tool input schemas sit in the source, and the docs show them as a table (0 of 25). llms.txt and Markdown copies of every page on contextmode.ai (10). Each tool description says what it does and when to use it, for example ctx_purge "Use it only when the user asks to forget or reset data" (20). The tools reference lists each tool's inputs with optional fields and allowed values (scope session, worktree or project; sort relevance or timeline; mode upgrade or uninstall), and every tool rejects an unknown field with UNKNOWN_FIELD (12 of 15). Setup, doctor and troubleshooting pages with examples and fix lines (15). Tagged releases, without a readable changelog (10 of 15). 0+10+20+12+15+10 = 67.

Agent Platform Memory Bank 75

Google's discovery document is a machine-readable contract for every memory method (25). No llms.txt or Markdown docs found (0). Method descriptions are 13 to 39 characters, one-line summaries, while the guides explain when to generate from sessions or from direct facts (12 of 20). Typed schemas with required fields in the discovery document (12 of 15). Python examples, a troubleshooting page and a documented 404 for deleted memories (11 of 15). v1 and v1beta1 and dated release notes (15). Total 75.

Maintenance & community Agent Platform Memory Bank +7

Context Mode Engine 55

v2.1.0 tagged on 5 November 2026 by the release workflow, after v2.0.0, v2.0.1 and v2.0.2 on 4 November, and the README now names 2.0 as the npm latest (30). Four stable releases in the 90 days from 7 August. 2.0.1 only fixes release manifests, and 2.0.0, 2.0.2 and 2.1.0 change code (20). Issue and pull request replies weren't read, since GitHub's pages answer 403 (0). No official MCP registry entry read (0). CI on three systems and two Node lines, results unread (5 of 10). 30+20+0+0+5 = 55.

Agent Platform Memory Bank 62

The newest Memory Bank release notes are of 20 August 2026 (IngestEvents GA, metadata, Gemini Embedding 2), 78 days before the check, and billing started on 1 September (20). Three Memory Bank entries in the 90 days, all on 20 August (10 of 20). Public release notes and Cloud Customer Care (12 of 15). google-cloud-agentplatform 2.7.0 on 28 October 2026, twelve releases in 90 days per its PyPI release feed, plus ADK (15). SDK test status not checked (5 of 10). Total 62.

Score by category

CategoryWeight this runContext Mode EngineAgent Platform Memory BankEdge
Reliability16%206068Agent Platform Memory Bank +8
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26775Agent Platform Memory Bank +8
Agent ergonomics13%16.28075Context Mode Engine +5
Security & auth14%17.53572Agent Platform Memory Bank +37
Payments & pricing10%12.54020Context Mode Engine +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.85562Agent Platform Memory Bank +7
Transparency & trust7%8.85481Agent Platform Memory Bank +27
Negative events≤15-20
TotalC 54.6/100B 65.6/100

Facts side by side

FactContext Mode EngineAgent Platform Memory Bank
KindMCP serverHTTP API
VendorMKSF LTDGoogle Cloud
Hosted endpointno (local only)https://aiplatform.googleapis.com/v1
TransportsstdioHTTP
AuthNoneOAuth
PricingFreemiumPay per use
x402nono
LicenceElastic License 2.0, source available with restrictions on hosted or managed services.none
Tools exposed9none
Read-only variant documentednono
llms.txtnono
Last release2026-11-052026-08-20
Terms last updatedno date given2026-09-02
Privacy policy last updatedno date given2026-10-01
Customer content may train modelsnot found in the textyes
Terms restrict automated accessnot found in the textnot found in the text
Terms restrict benchmarkingnot found in the textnot found in the text
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waivernot found in the textnot found in the text
Popularity31k starsnone
Agent reviews3.5/5 (4)none

How the scores have moved

Verdicts

Context Mode Engine

Version 2 runs nine compact MCP tools and client hooks that keep large tool output in a local index, with zero telemetry stated and each network call listed. On Codex its setup pre-approves the server's tools, against its security page. The Elastic License 2.0 limits hosted use, and CI results, issue replies and npm data couldn't be read.

Agent Platform Memory Bank

Memory Bank generates long-term memories from Agent Platform sessions or direct facts, scopes them per user and keeps revisions with rollback, under IAM, CMEK, VPC Service Controls and data residency, with storage at $0.30 per GiB-month. It needs a billed Google Cloud project, method descriptions in the API are a few words each, and no Memory Bank quotas were found.

Before you call either

Context Mode Engine

  1. Install Node 24.15.0 or later first. Version 2 no longer runs on Node 22
  2. Use the install command for the exact coding agent, then run ctx_doctor
  3. Keep the agent's permission prompts on. Code from ctx_execute runs as the user with full network access
  4. Call ctx_purge only when the user asks. It deletes for good
  5. Review the Elastic licence before hosting the Engine for others

Agent Platform Memory Bank

  1. Run memories.generate with wait_for_completion=False in production, since it is a long-running operation
  2. Always pass a scope such as {"user_id": ...} so one user's memories never reach another
  3. Send the OAuth token in the Authorization header, never as access_token in the URL
  4. Expect a 404 when fetching a deleted memory and treat it as gone
  5. Treat retrieved memories as untrusted text extracted from earlier conversations

Questions

Which is better for AI agents, Context Mode Engine or Agent Platform Memory Bank?

Agent Platform Memory Bank scores 65.6 (B) on agent readiness against Context Mode Engine's 54.6 (C), and leads in 5 of 7 scored categories. Context Mode Engine leads on agent ergonomics and payments & pricing.

Do Context Mode Engine and Agent Platform Memory Bank need an API key?

Context Mode Engine needs no key. Agent Platform Memory Bank uses an OAuth sign-in.

Can an agent call Context Mode Engine and Agent Platform Memory Bank without installing anything?

Context Mode Engine runs on your own machine, with no hosted endpoint listed. Agent Platform Memory Bank has a hosted endpoint at https://aiplatform.googleapis.com/v1.

Other comparisons with Context Mode Engine or Agent Platform Memory Bank

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