Harness Feature Management & Experimentation vs Mixpanel

Harness Feature Management & Experimentation 61

A closed service under Harness's subscription terms; the MCP server is MIT (18 of 30). The privacy statement covers website and sales data and defers customer data to the customer agreement and a published DPA; retention periods for customer data weren't found (18 of 30). A versioning policy for SDKs with support windows, and Split-era API endpoints marked deprecated with migration guides (14 of 20). Sub-processors are on the trust centre, which we didn't read, and the security page doesn't name data locations (10 of 20). 18+18+14+10 = 60.

Mixpanel 84

Closed service with public terms of use, last updated 2 June 2026. The SDKs are Apache-2.0 and Mixpanel Headless is MIT (16 of 30). The DPA of 2 June 2026 makes data available for 30 days after termination and then destroys it, and audit log retention is stated per plan. The privacy policy of 21 August 2026 covers only Mixpanel's own collection and names data centres in the US and EU, while the DPA adds India (24 of 30). Removals come with dated notices (Project Secret on 3 March 2027, TLS 1.0 and 1.1 in April 2026, US-to-EU forwarding in July 2026). No written policy with a minimum notice period was found (14 of 20). The sub-processor list, effective 21 October 2026, gives locations and names Anthropic, OpenAI and Google Vertex AI, with 30 days' notice of new sub-processors in the DPA (19 of 20).

Harness Feature Management & Experimentation 83

11 consolidated tools, and --toolsets=fme narrows the server to FME (25). Flag lists filter server-side by name, tag and rollout status, and the Admin API paginates with markerLimit (17 of 20). Documented status codes, 429 headers, and a harness_diagnose tool. Error bodies aren't documented per endpoint (14 of 20). harness_list and harness_get carry readOnlyHint, write tools ask for confirmation by elicitation, and harness_delete is marked destructive. No idempotency keys (15 of 20). Two required settings (API key, optional org and project, account ID read from the token); a Python Admin API wrapper and CLI, and SDKs in more than a dozen languages for evaluation (12 of 15). 25+17+14+15+12 = 83.

Mixpanel 61

The MCP page names 64 tools, which is over 30 (5), with OAuth scope subsets and a Get-Query-Schema tool that keeps the query schema out of the tool list (5 back, 10 of 25). Query endpoints take date ranges, limit and where filters, and profile queries page with page and session_id. No field selection was found (16 of 20). /import with strict=1 returns the failing events with reasons, and the MCP server's 401 says how to recover. Query API errors aren't in the spec (12 of 20). $insert_id deduplicates imports. No idempotency key was found for management writes, and we couldn't read the MCP tools' readOnlyHint or destructiveHint (10 of 20). Tracking SDKs in 12 languages and a Python SDK and CLI for queries, which is pre-1.0. Every query needs a project ID and the right regional host (13 of 15).

Harness Feature Management & Experimentation 15

No x402, MPP or L402 (0). No FME prices are published; harness.io/pricing lists FME only under Enterprise, priced by quotation (0). The docs describe a Start FME Free Plan step inside a Harness account; its limits and whether a card is needed aren't stated (15 of 20). A person signs up for Harness in a browser and creates a key or token (0). 0+0+15+0 = 15.

Mixpanel 37

Read with the hosted rubric. No x402, MPP or L402 (0). Prices are public without login. The docs give $0.00028 an event beyond the first 1M a month on the 1M Growth plan and the pricing page has a volume calculator. Enterprise is by quote, and the Query API limits on Free and Growth aren't given as figures (17 of 20). The Free plan covers 1M events a month with no card (20). A person signs up in a browser and approves OAuth or creates a service account. The MCP server supports dynamic client registration, but a user still signs in (0).

Harness Feature Management & Experimentation 80

Graded on the hosted FME Admin API with the hosted lines. Statuspage at status.harness.io with an FME component among 196 (20). In the 90 days from 8 August, two FME incidents: API write operations returned 499 errors for 30 minutes on 20 August (minor) and the FME user interface was unavailable for 15 minutes on 23 August (major, interface only; flag evaluation was unaffected per the post). No API outage of an hour or more (20 of 30). About 20 Admin API requests per 10 seconds per organisation and per IP, documented on the MCP page (15). 429 responses carry remaining and reset headers with guidance to wait for the larger reset, and the MCP server backs off and retries three times (15). No SLA was found on harness.io/pricing or the FME docs (0). FME is generally available and the MCP server is at 3.2.40 (10). 20+20+15+15+0+10 = 80.

Mixpanel 65

Read with the hosted lines, on the Query API and the hosted MCP server. www.mixpanelstatus.com is a Statuspage site with 11 components by region (20). Its history feed lists five incidents between 4 August and 2 November 2026. The Query API failed for US projects for about 77 minutes on 26 August, 2:02 to 3:19 PM PT per the post-mortem, when query servers "across the region failed their health checks nearly simultaneously" and reports were unavailable, with EU and India projects unaffected. US is the default data residency. A core API down across one region for an hour or more reads as a regional major, as vapi's US calls outage and google-drive-api's did. The others were confined to one host, tool or a subset and read as minor. Ingestion was delayed for US projects on 8 October, requests to decide.mixpanel.com failed on 21 October with the regional API hosts as a workaround, the MCP Get-Report tool failed with skip_results false on 6 August, and property menus misbehaved on 19 August. One major outage (10). Limits have numbers, 60 queries an hour and five concurrent on the Query API and 600 MCP requests an hour per user (15). The import docs give exponential backoff with jitter from 2 seconds to 60 for 429, 502 and 503, and $insert_id makes import retries safe. No Retry-After header was found in the reviewed documentation (12 of 15). No uptime SLA was found. Section 9.4 of the terms says the service isn't warranted to be always available (0). The APIs and the MCP server are generally available, with service account sign-in for MCP, the experiment and flag tools and Get-Audit-Log in beta (8 of 10). 20 + 10 + 15 + 12 + 0 + 8 = 65.

Harness Feature Management & Experimentation 79

Admin API keys with combinable roles that can't be widened after creation, Harness PATs and SATs for central management, and Harness Platform OAuth on the hosted MCP endpoint. Credentials travel in headers (28 of 30). HARNESS_READ_ONLY removes every write, writes go through elicitation with a risk threshold for auto-approval, and FME change requests add approval for flag changes (19 of 20). No prompt-injection guidance; the tools return flag names, descriptions and rule data written by people (3 of 15). FME admin, environment and object audit logs, plus structured MCP audit events to file, webhook or OpenTelemetry sinks (13 of 15). SOC 1 and SOC 2 Type II, ISO 27001, 27017 and 27018, FedRAMP 20x, a security@harness.io disclosure route with a 24-hour response, a private bug bounty on request and annual external penetration tests. No security.txt (16 of 20). 28+19+3+13+16 = 79.

Mixpanel 70

OAuth authorisation code with PKCE, dynamic client registration and 24 scopes for MCP. Service accounts are revocable, take a project role and can expire. The legacy Project Secret, one key for a whole project, stays valid on older projects until 3 March 2027 (26 of 30). Consumer and Analyst roles, custom roles on Enterprise, scope subsets and an organisation switch for MCP limit access. The MCP docs describe no read-only mode and no confirmation before Delete-Dashboard, Delete-Cohort or bulk edits (11 of 20). Event properties and replay data reach the model. The docs warn that data goes to the AI provider and give no prompt-injection guidance (3 of 15). MCP writes are logged with an origin of MCP on all plans for 90 days, with an audit log API and streaming on Enterprise. Reads and failed calls aren't logged (12 of 15). SOC 2 Type II, ISO 27001 and ISO 27701, a security.txt valid to 18 May 2027 and a private HackerOne programme. We didn't search NVD (18 of 20).

Harness Feature Management & Experimentation 71

No public OpenAPI file for the Admin API was found; the reference is a ReadMe site with a Postman collection. The MCP server's 11 tools have typed inputs, and harness_describe returns each FME resource's fields (18 of 25). llms.txt on both developer.harness.io and docs.split.io, and every page as Markdown with .md (10). The README describes each tool and when writes ask for confirmation; resource details sit behind harness_describe rather than in the tool text (13 of 20). The generic tools take a resource_type string and a body, so per-resource constraints aren't in the schema (8 of 15). An error-code page lists 400, 401, 402, 403, 404, 409 and 429 with causes, and docs carry curl examples (10 of 15). Tagged MCP releases and dated SDK versioning policy; the Admin API has v1 and v2 paths and deprecation notices for Split-era endpoints (12 of 15). 18+10+13+8+10+12 = 71.

Mixpanel 79

14 OpenAPI 3.0 and 3.1 specs are public at docs.mixpanel.com/openapi/ with 106 operations. The MCP tool schemas sit behind sign-in, so the API carries this line (25). llms.txt with about 530 links, llms-full.txt, a Markdown copy of every page and a docs MCP server (10). All 106 operations carry a summary or description, and the MCP page gives each tool one line with no guidance on when not to use it (15 of 20). The specs hold about 250 enums, but Query API calls pass JSON-encoded strings and where expressions in query parameters and JQL takes a script (10 of 15). Examples are present, the ingestion spec documents 400, 401, 413 and 429, and the Query spec documents only a 200 on all 19 operations (9 of 15). The changelog is public and dated with 183 entries. The APIs carry no dated versions, with paths such as /api/2.0 and /v1 (10 of 15).