diff --git a/plugin/scripts/search-server.cjs b/plugin/scripts/search-server.cjs
index b4311eb3..ac2f6273 100755
--- a/plugin/scripts/search-server.cjs
+++ b/plugin/scripts/search-server.cjs
@@ -543,7 +543,7 @@ Search workflow:
 1. Initial search: Use default (index) format to see titles, dates, and sources
 2. Review results: Identify which items are most relevant to your needs
 3. Deep dive: Only then use format: "full" on specific items of interest
-4. Narrow down: Use filters (type, dateRange, concepts, files) to refine results
+4. Narrow down: Use filters (type, dateStart/dateEnd, concepts, files) to refine results
 
 Other tips:
 \u2022 To search by concept: Use find_by_concept tool
diff --git a/plugin/skills/mem-search/SKILL.md b/plugin/skills/mem-search/SKILL.md
index 836272c3..732ee969 100644
--- a/plugin/skills/mem-search/SKILL.md
+++ b/plugin/skills/mem-search/SKILL.md
@@ -98,9 +98,9 @@ curl "http://localhost:37777/api/prompt/5421"
 **Filters (optional):**
 - `type` - Filter to "observations", "sessions", or "prompts"
 - `project` - Filter by project name
-- `dateRange[start]` - Start date (YYYY-MM-DD)
-- `dateRange[end]` - End date (YYYY-MM-DD)
-- `obs_type` - Filter observations by: bugfix, feature, decision, discovery, change
+- `dateStart` - Start date (YYYY-MM-DD or epoch timestamp)
+- `dateEnd` - End date (YYYY-MM-DD or epoch timestamp)
+- `obs_type` - Filter observations by type (comma-separated): bugfix, feature, decision, discovery, change
 
 ## Examples
 
@@ -111,7 +111,7 @@ curl "http://localhost:37777/api/search?query=bug&type=observations&obs_type=bug
 
 **Find what happened last week:**
 ```bash
-curl "http://localhost:37777/api/search?query=&type=observations&dateRange[start]=2025-11-11&format=index&limit=10"
+curl "http://localhost:37777/api/search?query=&type=observations&dateStart=2025-11-11&format=index&limit=10"
 ```
 
 **Search everything:**
diff --git a/plugin/skills/mem-search/operations/by-concept.md b/plugin/skills/mem-search/operations/by-concept.md
index 37d95642..14f642f3 100644
--- a/plugin/skills/mem-search/operations/by-concept.md
+++ b/plugin/skills/mem-search/operations/by-concept.md
@@ -28,7 +28,7 @@ curl -s "http://localhost:37777/api/search/by-concept?concept=discovery&format=i
 - **format**: "index" (summary) or "full" (complete details). Default: "full"
 - **limit**: Number of results (default: 20, max: 100)
 - **project**: Filter by project name (optional)
-- **dateRange**: Filter by date range (optional)
+- **dateStart/dateEnd**: Filter by date range (optional)
 
 ## When to Use Each Format
 
diff --git a/plugin/skills/mem-search/operations/by-file.md b/plugin/skills/mem-search/operations/by-file.md
index bdd0cfa8..d5daa887 100644
--- a/plugin/skills/mem-search/operations/by-file.md
+++ b/plugin/skills/mem-search/operations/by-file.md
@@ -24,7 +24,7 @@ curl -s "http://localhost:37777/api/search/by-file?filePath=src/services/worker-
 - **format**: "index" (summary) or "full" (complete details). Default: "full"
 - **limit**: Number of results (default: 20, max: 100)
 - **project**: Filter by project name (optional)
-- **dateRange**: Filter by date range (optional)
+- **dateStart/dateEnd**: Filter by date range (optional)
 
 ## When to Use Each Format
 
@@ -118,7 +118,7 @@ Response: "No observations found for 'nonexistent.ts'. Try a partial path or che
 1. Use format=index first to see overview of all changes
 2. Start with partial paths (e.g., filename only) for broader matches
 3. Use full paths when you need specific file matches
-4. Combine with dateRange to see recent changes: `?filePath=worker.ts&dateRange[start]=2024-11-01`
+4. Combine with dateStart to see recent changes: `?filePath=worker.ts&dateStart=2024-11-01`
 5. Use directory searches to see all work in a module
 
 **Token Efficiency:**
diff --git a/plugin/skills/mem-search/operations/by-type.md b/plugin/skills/mem-search/operations/by-type.md
index f5de6130..b659283c 100644
--- a/plugin/skills/mem-search/operations/by-type.md
+++ b/plugin/skills/mem-search/operations/by-type.md
@@ -27,7 +27,7 @@ curl -s "http://localhost:37777/api/search/by-type?type=bugfix&format=index&limi
 - **format**: "index" (summary) or "full" (complete details). Default: "full"
 - **limit**: Number of results (default: 20, max: 100)
 - **project**: Filter by project name (optional)
-- **dateRange**: Filter by date range (optional)
+- **dateStart/dateEnd**: Filter by date range (optional)
 
 ## When to Use Each Format
 
@@ -114,7 +114,7 @@ Fix: Use one of the valid type values
 
 1. Use format=index first to see overview
 2. Start with limit=5-10 to avoid token overload
-3. Combine with dateRange for recent work: `?type=bugfix&dateRange[start]=2024-11-01`
+3. Combine with dateStart for recent work: `?type=bugfix&dateStart=2024-11-01`
 4. Use project filtering when working on one codebase
 
 **Token Efficiency:**
diff --git a/plugin/skills/mem-search/operations/common-workflows.md b/plugin/skills/mem-search/operations/common-workflows.md
index 163d3a5c..d6f51419 100644
--- a/plugin/skills/mem-search/operations/common-workflows.md
+++ b/plugin/skills/mem-search/operations/common-workflows.md
@@ -186,7 +186,7 @@ Then choose anchor manually.
 
 1. **Combine filters** for precision:
 ```bash
-curl -s "http://localhost:37777/api/search/observations?query=authentication&type=feature&dateRange[start]=2024-11-01&format=index&limit=10"
+curl -s "http://localhost:37777/api/search/observations?query=authentication&type=feature&dateStart=2024-11-01&format=index&limit=10"
 ```
 
 2. **Review filtered results**
@@ -207,7 +207,7 @@ Found 10 authentication features added in November:
 
 **Why this workflow:**
 - Multiple filters narrow results before requesting full details
-- Type + query + dateRange = precise targeting
+- Type + query + dateStart/dateEnd = precise targeting
 - Progressive disclosure: index first, full details selectively
 
 ---
@@ -228,7 +228,7 @@ Found 10 authentication features added in November:
 1. **Start with index format** - Always use `format=index` first
 2. **Use specialized tools** - by-type, by-file, by-concept when applicable
 3. **Compose operations** - Combine search + timeline for investigations
-4. **Filter early** - Use type, dateRange, project to narrow before expanding
+4. **Filter early** - Use type, dateStart/dateEnd, project to narrow before expanding
 5. **Progressive disclosure** - Load full details only for relevant items
 
 ## Token Budget Awareness
diff --git a/plugin/skills/mem-search/operations/help.md b/plugin/skills/mem-search/operations/help.md
index 7092c7a0..93bf04df 100644
--- a/plugin/skills/mem-search/operations/help.md
+++ b/plugin/skills/mem-search/operations/help.md
@@ -106,9 +106,9 @@ Many endpoints share these parameters:
 - **limit**: Number of results to return
 - **offset**: Number of results to skip (for pagination)
 - **project**: Filter by project name
-- **dateRange**: Filter by date range
-  - `dateRange[start]`: Start date (ISO string or epoch)
-  - `dateRange[end]`: End date (ISO string or epoch)
+- **dateStart/dateEnd**: Filter by date range
+  - `dateStart`: Start date (YYYY-MM-DD or epoch timestamp)
+  - `dateEnd`: End date (YYYY-MM-DD or epoch timestamp)
 
 ## Error Handling
 
diff --git a/plugin/skills/mem-search/operations/observations.md b/plugin/skills/mem-search/operations/observations.md
index 97b65bfe..df5a7e1b 100644
--- a/plugin/skills/mem-search/operations/observations.md
+++ b/plugin/skills/mem-search/operations/observations.md
@@ -21,12 +21,12 @@ curl -s "http://localhost:37777/api/search/observations?query=authentication&for
 - **format**: "index" (summary) or "full" (complete details). Default: "full"
 - **limit**: Number of results (default: 20, max: 100)
 - **project**: Filter by project name (optional)
-- **dateRange**: Filter by date range (optional) - `dateRange[start]` and/or `dateRange[end]`
-- **obs_type**: Filter by observation type: bugfix, feature, refactor, decision, discovery, change (optional)
-- **concepts**: Filter by concept tags (optional)
-- **files**: Filter by file paths (optional)
+- **dateStart/dateEnd**: Filter by date range (optional) - `dateStart` and/or `dateEnd` (YYYY-MM-DD format or epoch timestamp)
+- **obs_type**: Filter by observation type (comma-separated): bugfix, feature, refactor, decision, discovery, change (optional)
+- **concepts**: Filter by concept tags (comma-separated, optional)
+- **files**: Filter by file paths (comma-separated, optional)
 
-**Important**: When omitting `query`, you MUST provide at least one filter (project, dateRange, obs_type, concepts, or files)
+**Important**: When omitting `query`, you MUST provide at least one filter (project, dateStart/dateEnd, obs_type, concepts, or files)
 
 ## When to Use Each Format
 
@@ -88,13 +88,13 @@ Search without query text (direct SQLite filtering):
 
 ```bash
 # Get all observations from November 2025
-curl -s "http://localhost:37777/api/search?type=observations&dateRange[start]=2025-11-01&format=index"
+curl -s "http://localhost:37777/api/search?type=observations&dateStart=2025-11-01&format=index"
 
 # Get all bug fixes from a specific project
 curl -s "http://localhost:37777/api/search?type=observations&obs_type=bugfix&project=api-server&format=index"
 
 # Get all observations from last 7 days
-curl -s "http://localhost:37777/api/search?type=observations&dateRange[start]=2025-11-11&format=index"
+curl -s "http://localhost:37777/api/search?type=observations&dateStart=2025-11-11&format=index"
 ```
 
 ## Error Handling
@@ -103,7 +103,7 @@ curl -s "http://localhost:37777/api/search?type=observations&dateRange[start]=20
 ```json
 {"error": "Either query or filters required for search"}
 ```
-Fix: Provide either a query parameter OR at least one filter (project, dateRange, obs_type, concepts, files)
+Fix: Provide either a query parameter OR at least one filter (project, dateStart/dateEnd, obs_type, concepts, files)
 
 **No results found:**
 ```json
diff --git a/plugin/skills/mem-search/operations/prompts.md b/plugin/skills/mem-search/operations/prompts.md
index 55d285df..3aa91609 100644
--- a/plugin/skills/mem-search/operations/prompts.md
+++ b/plugin/skills/mem-search/operations/prompts.md
@@ -21,7 +21,7 @@ curl -s "http://localhost:37777/api/search/prompts?query=authentication&format=i
 - **format**: "index" (truncated prompts) or "full" (complete prompt text). Default: "full"
 - **limit**: Number of results (default: 20, max: 100)
 - **project**: Filter by project name (optional)
-- **dateRange**: Filter by date range (optional)
+- **dateStart/dateEnd**: Filter by date range (optional)
 
 ## When to Use Each Format
 
@@ -99,7 +99,7 @@ Response: "No user prompts found for 'foobar'. Try different search terms."
 
 1. Use exact phrases in quotes: `?query="how do I"` for precise matches
 2. Start with format=index to see preview, then get full text if needed
-3. Use dateRange to find recent questions: `?query=bug&dateRange[start]=2024-11-01`
+3. Use dateStart to find recent questions: `?query=bug&dateStart=2024-11-01`
 4. Prompts show what was asked, sessions/observations show what was done
 5. Combine with session search to see both question and answer
 
diff --git a/plugin/skills/mem-search/operations/sessions.md b/plugin/skills/mem-search/operations/sessions.md
index 7da9a04c..b69b4765 100644
--- a/plugin/skills/mem-search/operations/sessions.md
+++ b/plugin/skills/mem-search/operations/sessions.md
@@ -21,7 +21,7 @@ curl -s "http://localhost:37777/api/search/sessions?query=authentication&format=
 - **format**: "index" (summary) or "full" (complete details). Default: "full"
 - **limit**: Number of results (default: 20, max: 100)
 - **project**: Filter by project name (optional)
-- **dateRange**: Filter by date range (optional)
+- **dateStart/dateEnd**: Filter by date range (optional)
 
 ## When to Use Each Format
 
@@ -102,7 +102,7 @@ Response: "No sessions found for 'foobar'. Try different search terms."
 
 1. Be specific: "JWT authentication implementation" > "auth"
 2. Start with format=index and limit=5-10
-3. Use dateRange for recent sessions: `?query=auth&dateRange[start]=2024-11-01`
+3. Use dateStart for recent sessions: `?query=auth&dateStart=2024-11-01`
 4. Sessions provide high-level overview, observations provide details
 5. Use project filtering when working on one codebase
 
diff --git a/plugin/skills/mem-search/principles/progressive-disclosure.md b/plugin/skills/mem-search/principles/progressive-disclosure.md
index 2de4f29e..7fcfa968 100644
--- a/plugin/skills/mem-search/principles/progressive-disclosure.md
+++ b/plugin/skills/mem-search/principles/progressive-disclosure.md
@@ -69,7 +69,7 @@ curl -s "http://localhost:37777/api/search/observations?query=authentication&for
 ### Step 4: Refine with Filters (If Needed)
 
 **Techniques:**
-- Use `type`, `dateRange`, `concepts`, `files` filters
+- Use `type`, `dateStart`/`dateEnd`, `concepts`, `files` filters
 - Narrow scope BEFORE requesting more results
 - Use `offset` for pagination instead of large limits
 
diff --git a/src/servers/search-server.ts b/src/servers/search-server.ts
index e58c8baf..c00345c8 100644
--- a/src/servers/search-server.ts
+++ b/src/servers/search-server.ts
@@ -127,7 +127,7 @@ Search workflow:
 1. Initial search: Use default (index) format to see titles, dates, and sources
 2. Review results: Identify which items are most relevant to your needs
 3. Deep dive: Only then use format: "full" on specific items of interest
-4. Narrow down: Use filters (type, dateRange, concepts, files) to refine results
+4. Narrow down: Use filters (type, dateStart/dateEnd, concepts, files) to refine results
 
 Other tips:
 • To search by concept: Use find_by_concept tool