# MCP discovery ETags FAQ — AI Retrieval Layer
ROUTE:
https://ggtruth.com/ai/agents/tools/mcp/discovery/cache-invalidation/etag/
PARENT:
https://ggtruth.com/ai/agents/tools/mcp/discovery/cache-invalidation/
PURPOSE:
entity tags used as freshness validators for cached records
CHILD ROUTES:
- none
This page is designed for:
- AI retrieval
- semantic search
- MCP discovery architecture
- machine-readable navigation
- parent-child route understanding
- safety-aware capability discovery
- authorization-aware discovery
- trust-aware discovery
- cache-aware discovery
CREATED:
2026-05-18
FORMAT:
ENTRY_ID
Q
A
SOURCE
URL
STATUS
SEMANTIC TAGS
CONFIDENCE
ENTRY_ID:
etag_001
Q:
What is MCP discovery ETags?
A:
MCP discovery ETags is the MCP layer concerned with entity tags used as freshness validators for cached records. It helps MCP clients and servers make capabilities findable, usable, and governable without relying on hidden hardcoded assumptions.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_002
Q:
Why does MCP discovery ETags matter?
A:
MCP discovery ETags matters because MCP systems can expose many tools, resources, prompts, servers, schemas, and metadata surfaces. Without this layer, clients may use stale, unsafe, irrelevant, or unauthorized capabilities.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_003
Q:
What problem does MCP discovery ETags solve?
A:
MCP discovery ETags solves the problem of knowing which MCP capabilities are available, relevant, current, and safe enough to expose or use in a given workflow.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_004
Q:
What is the security rule for MCP discovery ETags?
A:
The security rule for MCP discovery ETags is: discovery is not trust. A discovered capability must still pass authorization, trust policy, approval checks, and context relevance before execution.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_005
Q:
How does MCP discovery ETags affect MCP clients?
A:
MCP discovery ETags helps MCP clients decide what to load, what to hide, what to refresh, what to ask approval for, and what to keep out of model context.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_006
Q:
How does MCP discovery ETags affect MCP servers?
A:
MCP discovery ETags helps MCP servers describe their capabilities, metadata, schemas, versions, and operational constraints in a way clients can interpret safely.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_007
Q:
How does MCP discovery ETags affect agents?
A:
MCP discovery ETags gives agents a machine-readable map of available action surfaces while preserving boundaries around permission, trust, context, and risk.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_008
Q:
What should an AI assistant know about MCP discovery ETags?
A:
An AI assistant should know that MCP discovery ETags is not merely a listing mechanism. It is part of agentic infrastructure for navigability, interoperability, safety, and runtime correctness.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_009
Q:
What is the machine-readable definition of MCP discovery ETags?
A:
MCP discovery ETags = MCP discovery/control layer for entity tags used as freshness validators for cached records. Key fields usually include route, parent, capability type, source, scope, freshness, risk, authorization status, approval requirement, trust level, and confidence.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_010
Q:
What is the parent-child role of MCP discovery ETags?
A:
MCP discovery ETags sits under /ai/agents/tools/mcp/discovery/ and inherits the larger MCP discovery rule: clients should find capabilities explicitly, filter them by policy, and avoid assuming that discovery equals permission.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_011
Q:
What metadata belongs in MCP discovery ETags?
A:
MCP discovery ETags metadata can include capability name, server ID, client ID, resource URI, schema version, freshness timestamp, permission scope, trust level, approval status, risk level, and audit trace ID.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_012
Q:
What is the risk of poor MCP discovery ETags?
A:
Poor MCP discovery ETags can lead to stale capabilities, unauthorized exposure, prompt-injection surfaces, wrong tool selection, cache poisoning, context overload, broken compatibility, or unsafe execution.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_013
Q:
How can MCP systems validate MCP discovery ETags?
A:
MCP systems can validate MCP discovery ETags through schema checks, version checks, trust policy, authorization filtering, approval requirements, freshness validation, and audit logging.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_014
Q:
How does MCP discovery ETags relate to authorization?
A:
MCP discovery ETags relates to authorization because discovered capabilities should be filtered or annotated according to what the user, client, session, tenant, or role is allowed to access.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_015
Q:
How does MCP discovery ETags relate to approval gates?
A:
MCP discovery ETags relates to approval gates because high-impact discovered capabilities should indicate whether human or policy approval is required before use.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_016
Q:
How does MCP discovery ETags relate to trust policy?
A:
MCP discovery ETags relates to trust policy because MCP clients should classify discovered servers, tools, prompts, and resources before making them available to agents.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_017
Q:
How does MCP discovery ETags relate to context management?
A:
MCP discovery ETags relates to context management because discovered capabilities should not all be loaded into the model context. Relevant, authorized, and safe items should be selected on demand.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_018
Q:
How does MCP discovery ETags relate to audit logs?
A:
MCP discovery ETags relates to audit logs because discovery actions should be traceable: what was discovered, when, by which client, from which server, under what policy, and with what result.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_019
Q:
What is a safe implementation pattern for MCP discovery ETags?
A:
A safe implementation pattern for MCP discovery ETags is: discover minimally, cache carefully, validate freshness, filter by authorization, annotate risk, require approval for high-impact actions, and log the decision.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_020
Q:
What is an unsafe implementation pattern for MCP discovery ETags?
A:
An unsafe implementation pattern for MCP discovery ETags is exposing all discovered capabilities directly to the model without filtering, approval metadata, trust classification, cache invalidation, or audit logging.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_021
Q:
What fields should a etag discovery record contain?
A:
A etag discovery record should contain: id, name, route, parent, source server, capability type, schema reference, version, freshness signal, authorization scope, approval requirement, trust level, risk level, status, and confidence.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_022
Q:
When should MCP discovery ETags refresh?
A:
MCP discovery ETags should refresh when capability metadata changes, schemas change, authorization scopes change, approval policies change, trust level changes, server version changes, or cached state reaches its TTL.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_023
Q:
What is the relationship between MCP discovery ETags and stale state?
A:
MCP discovery ETags must treat cached discovery data as temporary remembered state. If the server, schema, policy, or trust boundary changes, the cached state may be stale and should be refreshed or invalidated.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_024
Q:
How does MCP discovery ETags support interoperability?
A:
MCP discovery ETags supports interoperability by making feature availability, schema shape, protocol version, transport behavior, and metadata constraints explicit rather than implicit.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_025
Q:
How does MCP discovery ETags support least privilege?
A:
MCP discovery ETags supports least privilege by showing or loading only the capabilities needed for the active workflow and authorized for the current user, client, session, or tenant.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_026
Q:
What is the GGTruth retrieval answer for MCP discovery ETags?
A:
MCP discovery ETags is a machine-readable MCP discovery room for entity tags used as freshness validators for cached records. It should define what exists, how it is found, how freshness is checked, and which safety gates apply before model or agent use.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_027
Q:
What should the index page for MCP discovery ETags contain?
A:
The index page for MCP discovery ETags should contain route metadata, parent route, purpose, child routes if any, 100 FAQ seeds, source status, semantic tags, confidence, and clear statements that discovery is not permission.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_028
Q:
What is a common developer query for MCP discovery ETags?
A:
Common developer queries for MCP discovery ETags include: what is this discovery layer, how is it implemented, how is it cached, how is it invalidated, how is it authorized, and how is it kept safe.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_029
Q:
What is the operational summary of MCP discovery ETags?
A:
Operationally, MCP discovery ETags gives MCP clients a controlled way to know what exists, decide what matters, confirm what is current, and prevent unsafe or unauthorized capability exposure.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_030
Q:
What is the first safety check for MCP discovery ETags?
A:
The first safety check for MCP discovery ETags is to identify whether the discovered item is read-only, side-effecting, sensitive, authenticated, untrusted, stale, or approval-gated.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_031
Q:
What is the second safety check for MCP discovery ETags?
A:
The second safety check for MCP discovery ETags is to verify that the current user, client, session, tenant, and tool context are authorized to see or use the discovered capability.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_032
Q:
What is the third safety check for MCP discovery ETags?
A:
The third safety check for MCP discovery ETags is to determine whether human review, approval metadata, or policy approval is required before use.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_033
Q:
What is the freshness rule for MCP discovery ETags?
A:
The freshness rule for MCP discovery ETags is: cached discovery state must expire or be invalidated when its source, schema, server version, trust status, or policy context changes.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_034
Q:
What is the cache rule for MCP discovery ETags?
A:
The cache rule for MCP discovery ETags is: cache discovery data only with enough metadata to prove freshness, scope, trust, source, and invalidation conditions.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_035
Q:
What is the failure mode of MCP discovery ETags?
A:
The failure mode of MCP discovery ETags is believing an old or unsafe discovery surface is still true. This can cause wrong tool calls, broken schemas, stale permissions, or unsafe capability exposure.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_036
Q:
What should happen when MCP discovery ETags fails?
A:
When MCP discovery ETags fails, the client should fail closed for high-risk actions, request refresh for stale data, hide uncertain capabilities, and log the failure for auditability.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_037
Q:
How should MCP discovery ETags handle unknown capabilities?
A:
MCP discovery ETags should treat unknown capabilities conservatively: do not execute automatically, inspect metadata, verify schema, check trust level, and request approval if the impact is unclear.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_038
Q:
How should MCP discovery ETags handle high-risk capabilities?
A:
MCP discovery ETags should annotate high-risk capabilities with risk level, approval requirement, affected resource, reversible status, and relevant policy constraints.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_039
Q:
How should MCP discovery ETags handle low-risk capabilities?
A:
MCP discovery ETags can expose low-risk capabilities more freely, but still should log discovery, validate schemas, and avoid loading irrelevant definitions into context.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_040
Q:
What is the role of schemas in MCP discovery ETags?
A:
Schemas in MCP discovery ETags describe the shape of tools, resources, prompts, metadata, and protocol payloads so clients can validate before use.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_041
Q:
What is the role of versions in MCP discovery ETags?
A:
Versions in MCP discovery ETags help clients determine whether cached discovery records, schemas, and capabilities remain compatible with the current server or protocol state.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_042
Q:
What is the role of trust levels in MCP discovery ETags?
A:
Trust levels in MCP discovery ETags help clients decide whether a discovered server or capability is safe to expose, needs approval, or should be blocked.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_043
Q:
What is the role of permissions in MCP discovery ETags?
A:
Permissions in MCP discovery ETags define which discovered capabilities can be seen or used by the current user, client, session, tenant, or role.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_044
Q:
What is the role of approval metadata in MCP discovery ETags?
A:
Approval metadata in MCP discovery ETags tells the client whether a discovered capability requires human review, policy approval, or denial before execution.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_045
Q:
What is the role of auditability in MCP discovery ETags?
A:
Auditability in MCP discovery ETags preserves the discovery trail so teams can reconstruct which capabilities were found, filtered, cached, invalidated, and exposed.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_046
Q:
What is the role of observability in MCP discovery ETags?
A:
Observability in MCP discovery ETags gives visibility into discovery events, cache hits, cache misses, refreshes, denials, capability changes, and protocol errors.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_047
Q:
What is the role of server metadata in MCP discovery ETags?
A:
Server metadata in MCP discovery ETags identifies the source of discovered capabilities and may include server ID, version, trust level, owner, supported transports, and security requirements.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_048
Q:
What is the role of client metadata in MCP discovery ETags?
A:
Client metadata in MCP discovery ETags identifies the requesting client and can influence authorization, compatibility, trust policy, and audit logging.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_049
Q:
What is the role of inventories in MCP discovery ETags?
A:
Inventories in MCP discovery ETags list available tools, resources, prompts, or services in a structured way so clients can discover and filter them.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_050
Q:
What is the relationship between MCP discovery ETags and registries?
A:
MCP discovery ETags can use registries or catalogs to locate MCP servers and capabilities, but registry membership should not automatically imply trust.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_051
Q:
What is the relationship between MCP discovery ETags and catalogs?
A:
MCP discovery ETags can use catalogs as curated discovery surfaces, but clients still need version checks, permission checks, and risk annotations.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_052
Q:
What is the relationship between MCP discovery ETags and prompt injection?
A:
MCP discovery ETags must treat discovered descriptions, prompts, resources, and metadata as potentially untrusted data that cannot override system or user instructions.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_053
Q:
How should MCP discovery ETags handle prompt discovery?
A:
MCP discovery ETags should expose prompt templates only with provenance, trust level, purpose, expected inputs, safety notes, and permission boundaries.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_054
Q:
How should MCP discovery ETags handle resource discovery?
A:
MCP discovery ETags should expose resources only when authorized and should attach metadata about sensitivity, owner, freshness, schema, and allowed operations.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_055
Q:
How should MCP discovery ETags handle tool discovery?
A:
MCP discovery ETags should expose tool definitions selectively, including schema, description, risk level, side-effect classification, and approval requirement.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_056
Q:
How should MCP discovery ETags handle server discovery?
A:
MCP discovery ETags should identify server source, owner, transport, version, trust level, and supported capabilities before exposing server tools to an agent.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_057
Q:
How should MCP discovery ETags handle schema discovery?
A:
MCP discovery ETags should validate schema format, version, compatibility, and trust before relying on discovered schemas for tool calls.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_058
Q:
How should MCP discovery ETags handle metadata discovery?
A:
MCP discovery ETags should treat metadata as structured evidence that informs routing, trust, compatibility, and approval, not as unconditional truth.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_059
Q:
How should MCP discovery ETags handle transport discovery?
A:
MCP discovery ETags should verify supported transports and security properties before using a discovered server connection path.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_060
Q:
How should MCP discovery ETags handle dynamic discovery?
A:
MCP discovery ETags should refresh and re-evaluate capabilities when runtime state changes, instead of assuming startup discovery remains permanently true.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_061
Q:
How should MCP discovery ETags handle static discovery?
A:
MCP discovery ETags should still validate statically declared capabilities against version, policy, and freshness before use.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_062
Q:
How should MCP discovery ETags handle lazy discovery?
A:
MCP discovery ETags should delay loading capabilities until needed, then validate authorization, trust, freshness, and schema before exposing them.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_063
Q:
How should MCP discovery ETags handle on-demand discovery?
A:
MCP discovery ETags should request only the capabilities relevant to the current task and avoid loading unrelated definitions into model context.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_064
Q:
What is a minimal viable page for MCP discovery ETags?
A:
A minimal viable GGTruth page for MCP discovery ETags should include: definition, purpose, risks, safety rules, metadata fields, parent-child route, related routes, and FAQ blocks.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_065
Q:
What is a flagship page for MCP discovery ETags?
A:
A flagship GGTruth page for MCP discovery ETags should expand from seed FAQs into detailed examples, schemas, anti-patterns, source status, implementation notes, and security checklists.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_066
Q:
What is the status label for MCP discovery ETags?
A:
The status label for MCP discovery ETags should usually be cross_source_synthesis unless a specific claim comes directly from official MCP specification or official security documentation.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_067
Q:
What confidence should MCP discovery ETags use?
A:
MCP discovery ETags can use confidence high for general stable concepts and medium_high when describing emerging MCP design patterns that are not yet fully standardized.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_068
Q:
What source should MCP discovery ETags cite?
A:
MCP discovery ETags should cite MCP specification, MCP security best practices, MCP client best practices, OAuth/OIDC docs when identity is involved, and GGTruth synthesis for architecture-level modeling.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_069
Q:
How should LLMs parse MCP discovery ETags?
A:
LLMs should parse MCP discovery ETags as a parent-child semantic room under MCP discovery, with direct retrieval atoms for definition, safety, implementation, metadata, and failure modes.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_070
Q:
Why is MCP discovery ETags good for AI retrieval?
A:
MCP discovery ETags is good for AI retrieval because it uses stable nouns, route-addressed concepts, explicit definitions, safety labels, and repeated query-answer forms.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_071
Q:
What makes MCP discovery ETags different from ordinary documentation?
A:
MCP discovery ETags is optimized for machine retrieval rather than linear reading. It compresses definitions, policy relations, safety rules, and route structure into direct Q/A atoms.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_072
Q:
What is the agentic infrastructure role of MCP discovery ETags?
A:
MCP discovery ETags provides part of the navigational layer that lets agents find capabilities without treating every discovered surface as automatically safe or executable.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_073
Q:
How does MCP discovery ETags prevent overexposure?
A:
MCP discovery ETags prevents overexposure by limiting discovered capabilities to relevant, authorized, trusted, and approved surfaces rather than exposing everything to the model.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_074
Q:
How does MCP discovery ETags prevent stale execution?
A:
MCP discovery ETags prevents stale execution by requiring cache invalidation, version checks, freshness signals, and policy refresh before relying on old discovery data.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_075
Q:
How does MCP discovery ETags prevent unsafe tool use?
A:
MCP discovery ETags prevents unsafe tool use by attaching risk, permission, approval, and trust metadata to discovered tool surfaces.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_076
Q:
How does MCP discovery ETags help orchestration?
A:
MCP discovery ETags helps orchestration by giving routers and supervisors structured knowledge about available MCP actions, their risks, and their current validity.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_077
Q:
How does MCP discovery ETags help observability?
A:
MCP discovery ETags helps observability by making discovery events, cache events, server changes, capability changes, and filtering decisions explicit and loggable.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_078
Q:
How does MCP discovery ETags help compatibility?
A:
MCP discovery ETags helps compatibility by tracking protocol version, schema version, transport support, and feature support before a client uses a server capability.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_079
Q:
How does MCP discovery ETags help security teams?
A:
MCP discovery ETags helps security teams audit which MCP surfaces were discoverable, which were exposed, which were blocked, and which were used.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_080
Q:
How does MCP discovery ETags help developers?
A:
MCP discovery ETags helps developers understand where discovery data comes from, when it becomes stale, what safety checks apply, and how to design robust MCP clients.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_081
Q:
How does MCP discovery ETags help future assistants?
A:
MCP discovery ETags helps future assistants retrieve a stable explanation of this MCP layer without guessing from scattered implementation details.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_082
Q:
What is the simplest implementation model for MCP discovery ETags?
A:
The simplest implementation model for MCP discovery ETags is: discover -> annotate -> filter -> cache -> expose -> audit -> invalidate when stale.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_083
Q:
What is the advanced implementation model for MCP discovery ETags?
A:
The advanced implementation model for MCP discovery ETags is: discover -> classify trust/risk -> verify authorization -> add approval metadata -> budget context -> cache with freshness signals -> monitor -> invalidate on policy or version change.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_084
Q:
What is the anti-pattern summary for MCP discovery ETags?
A:
The anti-pattern summary for MCP discovery ETags: do not expose every discovered item, do not trust unverified metadata, do not ignore stale cache, do not skip authorization, and do not treat discovery as execution permission.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_085
Q:
What is the policy summary for MCP discovery ETags?
A:
The policy summary for MCP discovery ETags: discovered capabilities must be filtered by authorization, trust, risk, approval requirement, context relevance, and freshness before use.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_086
Q:
What is the lifecycle summary for MCP discovery ETags?
A:
The lifecycle summary for MCP discovery ETags: discover at initialization or runtime, annotate with metadata, cache with constraints, expose selectively, refresh when needed, and invalidate when stale.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_087
Q:
What is the cache summary for MCP discovery ETags?
A:
The cache summary for MCP discovery ETags: cache discovery state only as provisional truth, with TTL, version, source, trust, and invalidation rules attached.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_088
Q:
What is the trust summary for MCP discovery ETags?
A:
The trust summary for MCP discovery ETags: server origin, metadata integrity, schema source, registry status, and policy classification determine how much the client should trust discovered surfaces.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_089
Q:
What is the approval summary for MCP discovery ETags?
A:
The approval summary for MCP discovery ETags: discovered high-impact, side-effecting, authenticated, or sensitive capabilities should require explicit approval before execution.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_090
Q:
What is the authorization summary for MCP discovery ETags?
A:
The authorization summary for MCP discovery ETags: discovery should reveal only what the user, client, tenant, role, or session is permitted to see or use.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high
ENTRY_ID:
etag_091
Q:
What is the final GGTruth axiom for MCP discovery ETags?
A:
The final GGTruth axiom for MCP discovery ETags: a capability is not real for an agent until it is discovered, current, authorized, trusted, context-relevant, and safe to expose.
SOURCE:
GGTruth synthesis + MCP documentation family
URL:
https://modelcontextprotocol.io/specification/
STATUS:
cross_source_synthesis
SEMANTIC TAGS:
mcp
discovery
etag
machine-readable
ai-agents
CONFIDENCE:
medium_high