configuration

🎛️ Configuration

Verdict: ServerBuilder exposes grouped Consumer<X.Builder> configurers + shorthand setters; buildConfig() yields immutable ServerConfig of records. Defaults tuned for local, stateless, loopback server.

🏗️ Builder groups

ServerBuilder ServerBuilder

Method	Target	Notes
info	ServerIdentity.Builder (api, Immutables)	name tachyon-mcp, version 0.1, title, description, websiteUrl, instructions, icons ServerIdentity
capabilities	CapabilitiesConfig.Builder	per-feature mode/listChanged/pageSize, completions, logging, tasks
session	SessionConfig.Builder	enabled, ttl, janitor, stores, id generator
network	NetworkConfig.Builder	host/port/address, endpoint, idle, body size, CORS, allowedHosts, ioEngine, heartbeat
runtime	RuntimeConfig.Builder (api)	shutdown grace, request timeout, clock
observability	ObservabilityConfig.Builder	slow-request log, listeners, payload capture
json	JsonConfig.Builder (api)	serde, input/output validators
name/version/host/port	shorthands
withTools/withResources/withPrompts/withCompletions	bootstrap registrations run in build()
withExtensions		dup id ⇒ IAE
threadFactory	handler executor
annotations	AnnotationContext (withProvider(p).register(obj))	composes across calls; @ExperimentalApi AnnotationContext
pipelineCustomizer	last Netty hook	@ExperimentalApi

📊 Defaults

Setting	Default	Proof
host	127.0.0.1	NetworkConfig#DEFAULT_HOST
port	-1 unset ⇒ start() ISE; 0 = ephemeral	NetworkConfig#UNSET_PORT, DefaultTachyonServer#start
endpoint	/mcp	DefaultTachyonServer
reader idle / writer idle	60s / 5min	DefaultTachyonServer
heartbeat	15s (≤0 disables)	DefaultTachyonServer
max body	1 MB	McpChannelInitializer#DEFAULT_MAX_CONTENT_LENGTH
ioEngine	AUTO	NetworkConfig#DEFAULT
sessions	disabled	SessionConfig#STATELESS
session TTL / janitor	30s / 5s	SessionConfig#DEFAULT_SESSION_TTL
feature modes	AUTO, listChanged false, page 50	FeatureConfig#DEFAULT, ResourcesConfig#DEFAULT
completions	AUTO	CapabilitiesConfig#DEFAULT
logging capability	false	same
tasks	disabled; keepAlive 5min	TasksConfig#DEFAULT_TASK_KEEP_ALIVE
shutdown grace / request timeout	5s / 60s	RuntimeConfig#shutdownGracePeriod
slow request log	MonitoringConfig.DEFAULT	tachyon-api/.../config/MonitoringConfig.java
payload capture	all off, 4096 bytes	PayloadCapturePolicy#DEFAULT_MAX_BYTES
validators / serde	networknt 2020-12 / Jackson	DefaultServerBuilder.java fields

🧷 Validation gotchas

• Builder annotation configurers (see declarative-configuration) compose into one server.annotations(...) call, using the constructed server's codecs (DefaultServerBuilder#applyAnnotationRegistrations). Spring defers discovered bean registration until singleton initialization; see spring-boot.

• SessionConfig: any session option while disabled ⇒ ISE "Session options require sessions to be enabled" SessionConfig#STATELESS, Builder#build.

• NetworkConfig.Builder: address() XOR host()/port() ⇒ ISE Builder#Builder.

• CapabilitiesConfig: tasks enabled w/o connector ⇒ ISE Builder#validateTaskConnector.

• page sizes must be > 0; maxContentLength > 0; pollInterval > 0.

• allowedHosts entries: bare authority only, no URL syntax ⇒ IAE at pipeline construction → security-guards.

Kotlin mirrors: info { }, capabilities { }, network { }, session { } scopes → tachyon-kotlin.

Related: overview, sessions, observability.

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_{📄 source .llm-wiki/concepts/configuration.md · updated 2026-09-15 · verified at 9eec1092 · tags [concept, config, builder]}