Signal catalog · 125 signals
Signals
Explore the browser surfaces measured by Introspection. Open a signal for a focused run, its source and reference.
Standalone tests contain the longer HTTP observations excluded from automatic captures.
Browsing this catalog does not run measurements. Each signal has a focused page; Workspace captures include the full catalog. Encrypted-media requests require an explicit action on their focused page.
browser.navigator
Navigator claims
Identity, privacy and automation flags reported by navigator; literal claims can disagree.
Open signal
browser.hardware
Reported hardware
Logical processors and approximate memory reported by this browsing context; these are browser claims.
Open signal
browser.languages
Language preferences
Primary language and the complete browser preference order; order and duplicates are meaningful.
Open signal
browser.locale
Locale and timezone
Intl default locale, calendar, numbering and timezone, with January/July offset observations.
Open signal
browser.client-hints
Client hints
Platform/mobile claims and all brands including GREASE. The existing collector sorts brands; original order is unavailable.
Open signal
browser.client-hints-high-entropy
High entropy hints
Architecture, model and version claims returned under browser policy; returned and missing keys stay explicit.
Open signal
browser.capabilities
API presence
Storage, rendering, worker and device API presence. Presence does not establish usability or permission.
Open signal
browser.plugins
Plugin metadata
Native ordered plugin and MIME metadata; metadata is separate from object and lookup semantics.
Open signal
browser.plugin-semantics
Plugin object semantics
Plugin identity, lookup, coercion and clone outcomes by operation, including bounded enumeration coverage.
Open signal
browser.language-availability
Language model availability
Reads the exposed language-model availability response without creating a model.
Open signal
browser.literal-metadata
Additional browser claims
Reads oscpu, SharedArrayBuffer exposure and validated heap-limit metadata.
Open signal
browser.platform-authenticator
Platform authenticator availability
Queries user-verifying platform authenticator availability without creating credentials.
Open signal
browser.policy-permissions
Policy and permission observations
Queries named permission states and exposed Permissions Policy decisions.
Open signal
browser.property-surface
Browser property surface
Reads named API and CSS property exposure and descriptors.
Open signal
display.screen
Screen geometry
Reported dimensions, available placement, depth, pixel ratio and orientation describe the active display environment.
Open signal
display.viewport
Viewport geometry
Window and visual viewport dimensions, scale and placement; changes across runs remain visible.
Open signal
display.touch
Touch support
Reported maximum touch points and touch API presence; these do not attest physical input hardware.
Open signal
display.media-preferences
Media queries
Theme, input, color and display-mode query responses retain parser evidence; a false match alone does not establish support.
Open signal
display.media-thresholds
Media query thresholds
Brackets selected media-query thresholds with explicit boundary controls.
Open signal
display.touch-construction
Touch event construction
Attempts synthetic TouchEvent construction and retains exposed and returned values.
Open signal
canvas.raster
Canvas raster
Complete 192 × 64 sRGB raster from fixed text and circles, with independent text width and fill-rule results.
Open signal
canvas.rendering
Canvas rendering
Full text rasters, opaque round trips, blank/space controls and sampled copy, crop, rotation, PNG, alpha, P3 and float16 paths retain rendering and conversion evidence.
Open signal
canvas.challenges
Canvas challenge consistency
Distinct A/B drawings on fresh and reused contexts, geometry-only outputs and opaque controls retain every measured raster.
Open signal
canvas.encoding
Canvas encoding
Encodes owned RGBA images through canvas encoders and retains exact output bytes.
Open signal
canvas.transfer-consistency
Canvas transfer consistency
Compares direct bitmap transfers with CPU-mediated transfers using owned pixels.
Open signal
webgl.raster
WebGL triangle
Fixed 32 × 32 WebGL1 triangle raster with renderer and capability observations from that same context.
Open signal
webgl.capabilities
WebGL capabilities
Independent WebGL1/2 renderer claims, extension membership, resource limits, shader precision and actual context attributes.
Open signal
webgl.arithmetic
WebGL arithmetic
Per-operation shader pixels, compile/link/readback controls and actual precision retain useful numeric differences.
Open signal
webgl.compressed-texture-response
Compressed texture response
Uploads owned compressed blocks and retains decoded pixel responses and controls.
Open signal
webgl.framebuffers
Framebuffer response
Negotiates bounded framebuffer formats and samples and retains readbacks and invalid controls.
Open signal
webgl.mipmap-response
Mipmap response
Generates mipmaps from owned base pixels and compares every retained level with explicit references.
Open signal
webgl.sample-coverage-response
Sample coverage response
Renders bounded sample-coverage conditions with endpoint controls and full readbacks.
Open signal
webgl.state-consistency
WebGL state consistency
Mutates and restores named WebGL states and checks owned readback scenes.
Open signal
webgl.translated-shaders
Translated shaders
Compiles owned GLSL shaders and reads bounded debug translations including invalid controls.
Open signal
webgpu.capabilities
WebGPU capabilities
Named GPU format/language, adapter and device claims retained independently of compute execution, with acquisition provenance and phase errors.
Open signal
webgpu.compute
WebGPU compute
Integer, float, subgroup and immediate readback challenges retain outputs and controls. Subgroup lane mapping is investigation evidence.
Open signal
webgpu.contention
GPU contention
Participation and successful-attempt distributions across four repeats per layout; scheduling order cannot establish identity.
Open signal
webgpu.rendering
WebGPU rendering
Renders owned GPU scenes and retains bounded mapped pixels and negotiated context.
Open signal
webgpu.sampling
WebGPU sampling
Exercises owned texture and sampler combinations with explicit controls.
Open signal
audio.filter-response
Biquad filter response
Magnitude and phase at eight fixed frequencies from an unrendered lowpass biquad; no audio output path is exercised.
Open signal
audio.rendering
Offline audio rendering
Sampled PCM windows by graph, sample rate and quantum, with actual quantum, suspension and residual controls.
Open signal
audio.latency
Audio latency hints
Latency-hint response staircase with actual sample rate, quantum and frame plateaus; suspended contexts do not establish a hardware path.
Open signal
audio.cancellation-response
Audio cancellation response
Compares compressor render paths and an exact cancellation control. Retains SHA-256 digests of little-endian float32 output with shape and control evidence.
Open signal
audio.decoding
Audio decoding
Decodes owned audio encodings and retains complete PCM responses.
Open signal
audio.direct-convolution
Direct audio convolution
Renders owned short convolution kernels with independent exact numeric references. Retains SHA-256 digests of little-endian float32 output with shape and control evidence.
Open signal
audio.encoder-configuration
Audio encoder configuration
Queries bounded Opus encoder configurations and returned settings.
Open signal
audio.encoding-response
Audio encoding response
Encodes owned PCM through Opus and retains encoded chunks and decoder metadata.
Open signal
audio.oversampling
Audio oversampling
Renders owned WaveShaper inputs with none, 2x and 4x oversampling and controls. Retains SHA-256 digests of little-endian float32 output with shape and control evidence.
Open signal
media.codecs
Codec capabilities
HTML and MSE playback responses and RTP sender/receiver codec parameters; video capability lists use semantic ordering, while audio retains returned order.
Open signal
media.decoding-capabilities
Media decoding capabilities
Queries supported, smooth and power-efficient responses for bounded media configurations.
Open signal
media.drm-capabilities
Encrypted media capabilities
Queries bounded key-system configurations without creating sessions or acquiring licenses.
Open signal
media.encoding
Video encoding
Encodes owned frames with bounded codec configurations and retains exact chunks.
Open signal
media.image-decoding
Image decoding
Exercises owned image fixtures through ImageDecoder and bitmap paths.
Open signal
media.recording
Media recording
Records an owned canvas stream and retains delivery witnesses and full bounded recording bytes.
Open signal
video.frames
Video frames
Per-codec sampled decoded planes and format/configuration, with independent orientation, crop and layout controls.
Open signal
video.decoder-response
Decoder response
Per-size and requested-preference decode correctness, sampled frames and completion response; requested preference is not observed acceleration.
Open signal
video.codec-realization
Video codec realization
Exercises owned VP8, H264 and HEVC clips through WebCodecs and HTML playback.
Open signal
video.color-conversion
Video color conversion
Copies owned video frames through explicit color-space and format paths.
Open signal
webrtc.loopback
Synthetic media loopback
Initial and renegotiated codec, dimensions and implementation observations with verified flow; packet counts and media time are reduced to flow validity.
Open signal
webrtc.offer-preferences
WebRTC offer preferences
Sets codec preferences and reads bounded local offer behavior.
Open signal
fonts.fallback-response
Font fallback response
Candidate and fallback font dimensions across fixed strings; width agreement alone is not proof of font installation.
Open signal
fonts.text-metrics
Text metrics
Exact Canvas text metric vectors and actual font settings across scripts and generic font families.
Open signal
fonts.shaping
Owned font shaping
Owned variable-font advances, DOM dimensions and wrapping remain independent, with axis/language context and actual reference controls.
Open signal
fonts.fallback-differentials
Font fallback differentials
Measures candidate font requests against generic fallback baselines.
Open signal
fonts.format-routing
Font format routing
Loads owned outline, COLRv0 and COLRv1 fonts and compares metrics and raster response.
Open signal
fonts.hyphenation
Hyphenation response
Measures line breaks with an owned uniform font and auto, none and manual controls.
Open signal
fonts.local-resolution
Local font resolution
Compares local-name lookup with positive, sentinel and negative controls.
Open signal
dom.geometry
DOM geometry
Box, native control, Range, SVG and MathML geometry in fixture-relative coordinates preserves translation and multiple rectangles.
Open signal
dom.xml
XML serialization
Namespace and XML roundtrip serialization retain permitted output variants and actual controls.
Open signal
dom.editing
Editing selection behavior
Moves and extends an owned text selection across character, word and document boundaries.
Open signal
dom.form-values
Native form values
Compares native form validity messages and values across owned language and input conditions.
Open signal
dom.layout-differentials
Layout differentials
Measures owned MathML, text, transform and accumulation cases with hidden and owned-font controls.
Open signal
css.system
CSS system rendering
Feature syntax support, system colors, system fonts and computed transforms are separate observations.
Open signal
css.arithmetic
CSS arithmetic
Integer arithmetic and syntax acceptance with explicit invalid controls retain exact computed results and residuals.
Open signal
css.color-paths
CSS color paths
Compares named colors through CSS resolution and canvas readback with literal controls.
Open signal
css.property-behavior
CSS property behavior
Measures bounded property assignment, support and computed behavior.
Open signal
svg.transforms
SVG transforms
Integer transform matrices and control outcomes reveal SVG transform behavior independently from CSS arithmetic.
Open signal
svg.filter-response
SVG filter response
Renders owned filter primitives and retains full bounded pixels and controls.
Open signal
svg.path-response
SVG path response
Measures owned path lengths and traversal against independent numeric references.
Open signal
javascript.math
Math numeric outputs
Exact Float64 bytes by operation with native and algebraic variants kept separate; no rounding alters equality.
Open signal
javascript.intl-formats
Intl formats
Locale-specific number/date/week output and resolved options, preserving exact Unicode and ordered format parts.
Open signal
javascript.url-normalization
URL normalization
URL and anchor parsing preserve Unicode, IDN/path normalization and expected invalid-input exception outcomes. File/drive/UNC inputs retain construction, canParse and absolute anchor outcomes with explicit bases.
Open signal
javascript.object-semantics
Object semantics
Property descriptors, receiver checks, language-array identity and expected exception names remain exact observations.
Open signal
javascript.intl-controls
Intl controls
Fixed formatting, segmentation and collation operations retain observed Unicode and permitted control variants.
Open signal
javascript.typed-arrays
Typed array conversions
Clamping, wrapping and alignment exceptions retain exact small conversion outcomes.
Open signal
javascript.binding-order
Native binding order
Ordered property names, descriptors and relative-order relationships by owner and realm preserve enumeration order.
Open signal
javascript.error-lookup
Error getter access
Getter topology and access counts before/logged/task/positive-control interventions; this does not identify a particular debugger.
Open signal
javascript.error-capture
Error allocation response
Error/plain allocation response by stack-limit and depth condition retains applied limits, counts and separate warm/measured aggregates.
Open signal
javascript.console-response
Console response
Allocation, serialization and task response by payload condition with counts and stop reasons; no inspector attribution is inferred.
Open signal
javascript.console-observation
Console observation callbacks
Records bounded Error, DOM and Proxy callbacks across console checkpoints and direct controls.
Open signal
javascript.function-continuity
Function continuity
Compares named functions and descriptors across top/frame contexts and two checkpoints.
Open signal
javascript.intl-data
Intl data behavior
Queries locale orderings, script display names and supported locales.
Open signal
javascript.keyboard-modifiers
Keyboard modifier semantics
Constructs Meta, Control and unmodified keyboard events and queries Accel.
Open signal
javascript.preview
Console formatter callbacks
Logs an owned object with custom formatters and records callbacks with a direct-call control.
Open signal
binary.numeric-representation
Float32 representation
Native Float32 bytes for finite, NaN and negative-zero values; byte representation does not identify a CPU model.
Open signal
binary.native-newlines
Native newlines
Blob/File native and transparent newline bytes across parts, contexts and worker transport retain exact small outputs.
Open signal
binary.gzip
Gzip encoding
Page/worker/chunking headers, complete compressed bytes and roundtrip/CRC validity remain separate conceptual fields.
Open signal
binary.float-conversions
Float16 conversions
Compares owned Float16 conversion paths, signed zero, rounding and NaN bytes.
Open signal
wasm.execution
Wasm execution
Exact scalar/SIMD lane bits, classes and allowed-result/repeat controls; compilation and execution timings are investigation evidence only.
Open signal
wasm.relaxed-instructions
Wasm relaxed instructions
Executes owned Wasm instruction fixtures with independent reference controls.
Open signal
wasm.response
Wasm execution checkpoints
Compiles owned Wasm and retains checked outputs and bounded timing blocks across repeated checkpoints.
Open signal
realms.lifecycle
Realm lifecycle
Document and WindowProxy preservation/replacement and worker continuity retain cross-realm claims; absolute time origins are excluded.
Open signal
realms.consistency
Cross-realm consistency
Actual navigator, Intl, numeric and descriptor values across top/frame/worker contexts remain available behind disagreement controls.
Open signal
realms.details
Detailed realm observations
Reads bounded identity, locale, API shape and high-entropy outcomes in fresh and reused realms.
Open signal
compute.work-scaling
Known-work scaling
Verified SHA-256 work response by workload/layout/load with validity, coverage and censoring; random digest answers are not fingerprints.
Open signal
compute.memory-response
Memory response
Verified dependent/sequential traversal response per working-set size, with separate warm/warmed aggregates and resolution validity.
Open signal
timing.scheduling
Scheduling response
Page/worker nested timers, message timers and tasks retain early/late summaries so clamping behavior remains visible.
Open signal
timing.async-response
Continuation response
Continuation correctness and warm/measured response per kind and depth; no universal instrumentation classifier is implied.
Open signal
timing.worker-startup
Worker startup
Fresh-worker readiness and steady message latency are reduced separately with counts, resolution and timeout censoring.
Open signal
network.transport
Network context
Service-reported OS/score and TCP characteristics describe the observed network path; a proxy can change them independently of browser rendering.
Open signal
speech.voice-inventory
Speech voice inventory
Snapshots available speech voices and bounded change-event behavior without speaking.
Open signal
crypto.key-admission
Cryptographic key admission
Imports bounded owned keys with valid and invalid usage and format controls.
Open signal
webgl.viewport-response
Viewport execution
Typed limits, clamping and analytic edge rendering on a tiny framebuffer; native small maxima are valid.
Open signal
audio.buffer-semantics
Audio buffer semantics
Storage, copying and long offline output with separate acquisition and short mixing controls.
Open signal
realms.worker-messaging
Worker message delivery
Three sequential protocols preserve the 250 ms checkpoint and later receipt independently; parent scheduling remains context.
Open signal
webgl.readback-layout
Readback destination layout
Known pixels, sentinel guards and PACK state across typed destinations and fenced pixel-pack buffers, including independent retrieval offsets.
Open signal
webgl.blending-response
Blending response
Raw RGBA8 direct and blended outputs; fractional conversion remains empirical.
Open signal
audio.data-layout
AudioData layout and ownership
Copy owned planar and interleaved dyadic samples into guarded destinations, then check clone and transfer lifetime. Evidence only; no detection or hardware attribution.
Open signal
webgl.transform-feedback
Transform feedback consistency
Capture exact vertex and instance records in separate and interleaved buffers; compare primitive counts, guards and a subsequent draw. Evidence only; no detection or hardware attribution.
Open signal
audio.channel-mixing
Executed channel mixing
Recover speaker and discrete channel matrices from isolated basis impulses, with identity and explicit routing controls. Evidence only; no detection or hardware attribution.
Open signal
audio.param-automation
Audio parameter automation
Render scheduled gain trajectories at a-rate and k-rate; reconcile hold cancellation with an equivalent authored history. Evidence only; no detection or hardware attribution.
Open signal
audio.analyser-response
Audio analyser response
Observe finite offline audio at recorded suspension frames through float and byte time and frequency accessors. Evidence only; no detection or hardware attribution.
Open signal
audio.recursive-filter
Recursive audio filter response
Compare executed impulse recurrence with frequency queries on the same IIR node, including scaled coefficients and delayed inputs. Evidence only; no detection or hardware attribution.
Open signal
webgpu.texture-views
Texture view interpretation
Read the same 8 by 2 texture through linear and sRGB views and raw copies across repeated uploads and view recreation. Evidence only; no detection or hardware attribution.
Open signal
css.transform-interpolation
Stopped transform interpolation
Seek stopped animations to five fixed times and reconcile computed matrices, bounds and direct styles across reference-box changes. Evidence only; no detection or hardware attribution.
Open signal