diff --git a/packages/api/src/utils/common.ts b/packages/api/src/utils/common.ts
index 0888f8c87..293a72354 100644
--- a/packages/api/src/utils/common.ts
+++ b/packages/api/src/utils/common.ts
@@ -1,6 +1,16 @@
+export type JSONBlob = Record<string, Json>;
+
+export type Json =
+  | string
+  | number
+  | boolean
+  | null
+  | Json[]
+  | { [key: string]: Json };
+
 export const useTry = <T>(fn: () => T): [null | Error | unknown, null | T] => {
-  let output: T | null = null;
-  let error: any = null;
+  let output: null | T = null;
+  let error: null | Error | unknown = null;
   try {
     output = fn();
     return [error, output];
@@ -10,9 +20,7 @@ export const useTry = <T>(fn: () => T): [null | Error | unknown, null | T] => {
   }
 };
 
-export const tryJSONStringify = (
-  json: Record<string, unknown> | Record<string, unknown>[],
-) => {
+export const tryJSONStringify = (json: Json) => {
   const [_, result] = useTry<string>(() => JSON.stringify(json));
   return result;
 };
diff --git a/packages/api/src/utils/logParser.ts b/packages/api/src/utils/logParser.ts
index 9041cfd05..1e96488d8 100644
--- a/packages/api/src/utils/logParser.ts
+++ b/packages/api/src/utils/logParser.ts
@@ -1,9 +1,7 @@
 import _ from 'lodash';
 
+import type { Json, JSONBlob } from './common';
 import { tryJSONStringify } from './common';
-
-export type JSONBlob = Record<string, any>;
-
 export type KeyPath = string[];
 
 export enum AggregationTemporality {
@@ -85,7 +83,7 @@ export function* traverseJson(
   currentNode: JSONBlob,
   depth = 1,
   keyPathArray?: KeyPath,
-): IterableIterator<[KeyPath, any]> {
+): IterableIterator<[KeyPath, Json]> {
   for (const [key, value] of Object.entries(currentNode)) {
     const keyPath = keyPathArray ? [...keyPathArray, key] : [key];
 
@@ -119,7 +117,7 @@ export const mapObjectToKeyValuePairs = (
   const pushArray = (
     type: 'bool' | 'number' | 'string',
     keyPath: string,
-    value: any,
+    value: number | string, // Note that booleans are converted to 0 or 1
   ) => {
     const keyNames = `${type}.names`;
     const keyValues = `${type}.values`;
@@ -229,14 +227,11 @@ export type VectorMetric = {
   v: number; // value
 };
 
-abstract class ParsingInterface<T> {
-  abstract _parse(
-    log: T,
-    ...args: any[]
-  ): LogStreamModel | MetricModel | RrwebEventModel;
+abstract class ParsingInterface<T, S> {
+  abstract _parse(log: T, ...args: any[]): S;
 
   parse(logs: T[], ...args: any[]) {
-    const parsedLogs: any[] = [];
+    const parsedLogs: S[] = [];
     for (const log of logs) {
       try {
         parsedLogs.push(this._parse(log, ...args));
@@ -249,7 +244,7 @@ abstract class ParsingInterface<T> {
   }
 }
 
-class VectorLogParser extends ParsingInterface<VectorLog> {
+class VectorLogParser extends ParsingInterface<VectorLog, LogStreamModel> {
   getType(log: VectorLog): LogType {
     if (log.hdx_platform === LogPlatform.OtelTraces) {
       return LogType.Span;
@@ -282,10 +277,10 @@ class VectorLogParser extends ParsingInterface<VectorLog> {
   }
 }
 
-class VectorMetricParser extends ParsingInterface<VectorMetric> {
+class VectorMetricParser extends ParsingInterface<VectorMetric, MetricModel> {
   _parse(metric: VectorMetric): MetricModel {
     return {
-      _string_attributes: metric.b,
+      _string_attributes: metric.b as any, // TODO: fix conversion of metric.b to proper string map
       data_type: metric.dt,
       is_delta: metric.at === AggregationTemporality.Delta,
       is_monotonic: metric.im,
@@ -297,7 +292,7 @@ class VectorMetricParser extends ParsingInterface<VectorMetric> {
   }
 }
 
-class VectorRrwebParser extends ParsingInterface<VectorLog> {
+class VectorRrwebParser extends ParsingInterface<VectorLog, RrwebEventModel> {
   _parse(log: VectorLog): RrwebEventModel {
     return {
       ...mapObjectToKeyValuePairs(log.b),