Abyssale vs PostNitro

Abyssale 98

A 424 KB OpenAPI file at developers.abyssale.com/api.yaml with 34 operations, from which the reference pages are generated (25). A detailed llms.txt that states the base URL, auth, rate limits, error envelope and webhook signing up front (10). Pages say what each endpoint is for and when to use another, such as synchronous versus asynchronous generation and designs versus workspace templates, and the MCP permissions page says what each tool can break (19 of 20). Typed parameters with enums, ranges and required fields across layers and formats (14 of 15). One error envelope everywhere, an error catalogue with machine-readable ids and what to do for each, and worked examples (15). Date-based versions named in every response and a dated changelog in Keep a Changelog form with a Breaking section first; the MCP server has its own semver changelog (15). 25 + 10 + 19 + 14 + 15 + 15 = 98.

PostNitro 77

OpenAPI 3.1 document for the Embed API at /.well-known/openapi/embed.json, with 13 operations per the 14 October check and not re-read. The MCP docs now point to a public tool catalogue on the MCP host with every tool's input and output schema, which we didn't request, so the earlier partial is held (20). llms.txt (updated 29 October 2026), llms-full.txt, a docs llms.txt and .md twins (10). The docs state what each tool is for, when not to use PostNitro and the embedPostId and designId split, and the tool count now reads 40 on every page read (15). 24 enums, typed slide objects and per-platform settings with conditional rules per the 14 October check, and unknown keys in settings objects are now refused by name (12). Examples on each page and a full table of validation messages for the Schedule API (13). info.version 1.0.0 with no version in the path and no API changelog. The CLI has a dated Keep a Changelog file with semver (7). 20 + 10 + 15 + 12 + 13 + 7 = 77.

Abyssale 85

API version v2026-10-29, eight days before this check (30). Fifteen dated API versions between 21 August and 29 October, MCP server releases 1.0.0 (1 September) to 1.2.0 (7 October), and SDK releases in October (20). Closed service with a changelog and RSS feed, help@abyssale.com and in-app chat, which we didn't test (12 of 15). com.abyssale/mcp is in the official MCP registry under a domain-verified namespace, and the Node.js (1.9.0) and Python (1.7.0) SDKs were both released on 21 October 2026 (15). Both SDKs are current; their repositories weren't read (8 of 10). 30 + 20 + 12 + 15 + 8 = 85.

PostNitro 65

CLI 1.6.0 tagged on 1 November 2026, with motion styles, post read and edit and an AI voiceover, against an Embed API release it names (30). CLI 1.3.0 (tagged 19 August), 1.4.1 (29 September), 1.5.0 (7 October) and 1.6.0 (1 November) fall in the 90 days, read from the repository's tags and changelog (20). Closed service with a dated CLI changelog, support by email and in-app chat, and public repositories with few outside contributions to judge replies by (8). No official MCP registry entry could be read, and the server card's ai.postnitro/mcp is a claim (0). The CLI publishes from a GitHub Actions workflow. The Embed SDK was last published on 15 July 2025, per the 14 October check (7). 30 + 20 + 8 + 0 + 7 = 65.

Abyssale 85

20 MCP tools (15 for 11 to 30), plus 5 because OAuth scopes per tool group let a client be approved for reads only (20 of 25). Design listings search by words in any order, filter by project, orientation, size, format and dates, sort and order, and say honestly when a page is past the end; listing tools refuse unsupported options rather than ignore them, per MCP 1.2.0 (19 of 20). One envelope with an id to branch on, and error docs that say which errors a retry never fixes (19 of 20). The permissions page marks each tool read-only, mutating or destructive, but MCP annotations couldn't be confirmed on the closed server, and generation has no idempotency key (12 of 20). Official Node.js and Python SDKs with retry behaviour and polling helpers (15). 20 + 19 + 19 + 12 + 15 = 85.

PostNitro 68

40 MCP tools load together on the main server URL (5). A read-only server URL serves only the 16 tools annotated readOnlyHint, the DESIGN output skips rendering and the _and_wait tools fold polling into one call (8 back, 13). Templates and brands page with page and limit up to 100, and scheduled posts filter by date range and social account (14). API errors reach the agent verbatim with their status and a plain message, the schedule error page lists every validation message, unknown keys are refused by name, and a missing ID returns the candidate IDs. A brand-limit error comes back as 401, per the 14 October check (14). Every create tool takes an idempotencyKey, and the MCP docs say every tool carries readOnlyHint and destructiveHint, naming the six destructive tools (20). Saved defaults and single-candidate auto-selection keep required arguments to one or two. Official code is a Node CLI and a browser editor SDK, one language (7). 13 + 14 + 14 + 20 + 7 = 68.

Abyssale 35

No x402, MPP or L402 (0). Seat prices are public and the credit cost of every output is published to the format, with worked examples, but a credit's price outside the plan wasn't found (15 of 20). 14-day free trial with no card (20). A person signs up in the browser; the MCP OAuth flow needs a human login (0). 0 + 15 + 20 + 0 = 35.

PostNitro 20

No x402, MPP or L402 (0). Credit prices are public without a login at $0.04 a credit, 1 per imported slide and 2 per AI-written slide, with plan prices of $15, $30 and $60 a month (20). The web app has a free plan with no card, but the subscription docs, the MCP docs and llms.txt now agree there is no free API tier, and calls without a paid plan return 402 (0). A person signs up in a browser and generates a key, or approves OAuth in the client. Dynamic client registration removes the key step but not the signup (0). 0 + 20 + 0 + 0 = 20.

Abyssale 71

Closed service under terms of service version 3 of 21 July 2026, from a Paris SAS with its register number (15). The privacy policy and terms agree on EU hosting on AWS Ireland, deletion timelines and breach notice within 72 hours, but AI model training on anonymised customer content is on by default with a workspace opt-out, and anonymised data may be kept indefinitely (20 of 30). The changelog has Deprecated and Removed sections and refers to a deprecation policy that covers stable endpoints but not alpha ones; the policy's notice period wasn't found (14 of 20). Subprocessors named with locations, among them AWS Ireland, Auth0, Brevo, Intercom and AI providers including OpenAI, Anthropic, Black Forest Labs and Google, some outside the EEA (20). 15 + 20 + 14 + 20 = 69.

PostNitro 58

Closed service under Terms of Service last updated 20 May 2024, re-read on 5 November, that cover the APIs, allow changes or discontinuation without notice and take a perpetual licence to user content to run the service. The terms name no legal entity or governing law (12). The privacy policy, updated 2 November 2026, corrects its Use of Data section and now says PostNitro doesn't train AI models on user content, in line with the Claude page. Personal data is kept while the account is active and deleted within 24 hours of a request. No DPA (14). The fact sheet dates the withdrawal of the Creator and Team plans and existing subscribers keep them. The CLI changelog marks API-version dependencies. No deprecation policy for the API (8). The policy names UserMaven and CrispChat and an unnamed payment processor, the docs name Lemon Squeezy for billing, and no data locations were found (5). 12 + 14 + 8 + 5 = 39.