Hydrostor
Hydrostor is a Canadian long-duration energy storage developer founded in 2010 and headquartered in Toronto, with offices in Denver, Colorado and Melbourne and Adelaide, Australia. It builds and operates Advanced Compressed Air Energy Storage (A-CAES) facilities: surplus grid electricity runs a compressor, the heat of compression is captured and stored, and the cooled compressed air is sent into a purpose-built underground cavern held at constant pressure by a water column. On discharge the water weight pushes the air back to surface, where it is recombined with the stored heat and expanded through a turbine, giving eight or more hours of emissions-free storage from a plant with a multi-decade asset life. The company is backed by Goldman Sachs Alternatives, CPP Investments, the Canada Growth Fund, Canoe Financial and Arctern Ventures, operates a commercially contracted utility-scale facility in Goderich, Ontario, and is advancing a roughly 7 GW pipeline including the Willow Rock and Copper Valley centers in California, Silver City in New South Wales, and Quinte and Wellington in Ontario. Hydrostor is an energy infrastructure developer rather than a software vendor: it publishes no developer portal, no SDKs, no product API and no machine-readable specification of its own. The only machine-readable interface it exposes is the WordPress core REST content API behind hydrostor.ca, which is anonymously readable, read-only without credentials, and carries the project portfolio, the newsroom archive and the media library. That surface is profiled here for discovery purposes and is described from the site's own self-describing route index.
Limited machine-readable signal and partial portal coverage — documentation a human can read, but little a machine or agent can consume without scraping.
API Evangelist profiles Hydrostor the way a machine reads it — 14 machine-readable artifacts across 9 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Hydrostor scores 36.0/100 (thin), with a separate agent-readiness read of 48/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.
Kin Score
How this is scored →scored 2026-08-24 · rubric v0.12.1
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How we profile Hydrostor
Each block below is one kind of artifact we hold for Hydrostor. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
APIs 9
Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.
Individual APIs this provider publishes, each with its own machine-readable definition.
Hydrostor Projects API
Public, unauthenticated read access to Hydrostor's Advanced Compressed Air Energy Storage project portfolio — the site-specific `project` custom post type behind hydrostor.ca/pr...
Hydrostor Posts API
Public, unauthenticated read access to the Hydrostor newsroom archive — press releases, company insights and featured media coverage — via the WordPress core REST API behind hyd...
Hydrostor Pages API
Public, unauthenticated read access to the static marketing and policy pages of hydrostor.ca — the company, technology and geology explainers, the project index, use cases, care...
Hydrostor Media API
Public, unauthenticated read access to the media library behind hydrostor.ca — project renders, facility and geology photography, technology diagrams and press assets, each with...
Hydrostor Taxonomy API
Public, unauthenticated read access to the classification vocabularies behind hydrostor.ca: newsroom categories and tags, plus the site-specific `project_category` and `project_...
Hydrostor Search API
Public, unauthenticated cross-content search over hydrostor.ca — newsroom posts, static pages and the A-CAES project portfolio in one result set, each result carrying its id, ti...
Hydrostor Discovery API
Public, unauthenticated discovery metadata for hydrostor.ca — the self-describing route index (340 routes across 18 namespaces at capture), the registered content types and taxo...
Hydrostor oEmbed API
Public oEmbed 1.0 provider endpoint for hydrostor.ca URLs, returning embeddable rich metadata — title, author, thumbnail and iframe HTML — for any newsroom post, static page or ...
Hydrostor SEO Metadata API
Public Yoast SEO head endpoint returning the rendered head metadata and its parsed schema.org JSON-LD graph for any hydrostor.ca URL — a structured-data view of every newsroom p...
Scroll within the panel for all 9 ·
Pricing Plans 1
Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the things the Kin Score reads for access clarity — renamed from commercial clarity in rubric 0.12, because a free statutory interface has access terms and no commercial ones.
Published pricing tiers and plan structures.
Rate Limits 1
Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.
Documented rate limits and quota policies.
Hydrostor Rate Limits
RATE LIMITSSecurity Posture 2
Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.
Recommended x-agentic-access execution contracts for AI agents.
Resources
Every other property we hold for Hydrostor — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Agent Surfaces 3
MCP servers, agent skills, and machine-readable catalogs
Design & Contract 5
Pagination, idempotency, versioning, errors, and events
Build 3
SDKs, sample code, and the tooling you integrate with
Access & Security 3
Authentication, authorization, and security posture
Learn 1
Tutorials, courses, talks, and written guidance
Operate 2
Status, limits, changes, and where to get help
Commercial 3
Pricing, plans, and the legal terms of use
Company 7
The organization behind the API
Scroll within the panel for all 7 ·
Other 5
Properties that don't map to a standard resource type
← All providers · Data indexed from github.com/api-evangelist/hydrostor · machine-readable index on apis.io
This is an independent, third-party profile of Hydrostor, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.
The Kin Score and Agent Readiness rating are independently calculated assessments of a company's public API artifacts, scored against a published rubric. They are not certifications, endorsements, security assessments, or audits.
Corrections, re-scores, and removal are free — no partnership or purchase required, and you do not need to justify the request. A removed company is recorded as unrated, never scored zero for having asked. Acknowledgement within one business day; removal within two.
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you will get a person, not a form — we will tell you exactly which public URLs this profile was built from.