tachyon api

📜 tachyon-api

Verdict: contract module. User-facing SAMs, descriptors, requests, results, domain content types, runtime context, JSON SPI, stability annotations. No Netty, no Jackson in public signatures.

🗂️ Packages (tachyon-api/src/main/java/dev/tachyonmcp/api/)

Package	Key types	Page
annotations	ExperimentalApi, InternalApi, LegacyApi; declarative McpTool, McpResource, McpPrompt, McpCompletion	api-stability, declarative-configuration
json, json.spi	JsonDocument, JsonObject, JsonArray, JsonSchema, JsonSchemaValidator, PayloadSerde, JsonDocumentFactory, JsonSchemaFactory	json-layer
runtime	InteractionContext, ContextNotifications, Notifications, ClientContext (elicitation, legacy sampling), AttributeKey, Extension	below
server	ServerFeature<D> (descriptor()), ServerFeature.Descriptor (name()), .Request extends HasMeta
server.config	ServerIdentity, RuntimeConfig, JsonConfig, MonitoringConfig, Mode	configuration
server.domain	ContentBlock sealed (TextContent, ImageContent, AudioContent, ResourceLink, EmbeddedResource), ResourceContents (text/blob), Args, RequestId, ProgressToken, LoggingLevel, ServerError, ServerCapabilities, UriTemplate, InputRequest (FormInputRequest, UrlInputRequest), InvalidArgumentException, Icon, Annotations, ToolAnnotations
server.extensions	ServerExtension, ExtensionContext, ExtensionMethodHandler, ExtensionSettings, AdvertiseMode	extensions
server.features	HandlerFutures (@InternalApi), PaginatedResult	feature-registries
server.features.tools	Tools, ToolFn, AsyncToolFn, TypedToolFn, AsyncTypedToolFn, ToolHandler, AbstractToolHandler, ToolDescriptor, ToolRequest, ToolResult	feature-registries
server.features.resources	Resources, ResourceFn, AsyncResourceFn, ResourceDescriptor, ResourceTemplateDescriptor, ResourceRequest
server.features.prompts	Prompts, PromptFn, AsyncPromptFn, PromptDescriptor, PromptRequest, PromptResult
server.features.completions	Completions, CompletionFn, AsyncCompletionFn, CompletionRequest, CompletionResult
server.features.tasks	Tasks, TaskConnector, TaskSnapshot, TaskState, TaskSupport, Task*Fn, Task*Request, TaskNotFoundException	tasks
server.features.annotations	AnnotationProvider, AnnotationRegistrationContext, AnnotationInvocationSupport	declarative-configuration
server.session	SessionIdGenerator<T>	sessions

🎭 InteractionContext (what handlers get)

InteractionContext: protocolVersion(), lifecycle() (INITIALIZATION|OPERATION|SHUTDOWN), sessionId() (null stateless), isExtensionEnabled(id), notifications() (log, progress(token,…), comment), client() (elicitation().create(...)), sendRequest(method, params) (@ExperimentalApi, raw JSON string future), typed attributes get/set(AttributeKey).

Runtime impl in core: DefaultDispatchContext (per request, wraps channel ctx) → tachyon-core.

📝 Elicitation values

ElicitationRequest#builder and ElicitationResult#builder are records: canonical constructors stay for source/binary compatibility with published betas. Both add of(...) and a hand-written Builder with from; request message/schema and result action are required (compact ctor requireNonNull), result content is nullable.

🎁 Results

• ToolResult sealed Success | Error | InputRequired | Task + statics text, content, structured(payload[, text]), error, empty, task, raw(json,text), inputRequired(reqs, state) ToolResult.
• PromptResult sealed Messages | InputRequired PromptResult.
• InputRequired (MRTR: inputRequests map + opaque requestState); follow-up request carries inputResponses + requestState (ToolRequest#arguments).

🧪 Tests

tachyon-api/src/test/java/dev/tachyonmcp/api/ — JsonObjectTest, JsonSchemaTest, ArgsTest, UriTemplateTest, ToolResultTest, HandlerFnContractTest, HandlerFuturesTest, descriptor tests.

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_{📄 source .llm-wiki/modules/tachyon-api.md · updated 2026-09-15 · verified at b1aeff64 · tags [module, api]}