diff --git a/DESCRIPTION b/DESCRIPTION
index 7272859..8457d98 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,27 +1,28 @@
-Package: PallasExplorer
-Type: Package
-Title: Sparql Graph construction and object Auto-suggestion 
-Version: 0.0.0.9000
-Authors@R: c(
-    person(
-      "Ata", "Badr Barzegar",
-      email = "atabadrbarzegar@gmail.com",
-      role = c("aut", "cre")
-    )
-  )
-Description: The main goal is to connect to SPARQL endpoints and bering their structure into the R world. This package would enable R developers to make a graph of RDF schemas in different endpoints and also access classes and properties with auto-suggestion mechanism enabled in R.  
-License: MIT + file LICENSE
-Encoding: UTF-8
-Roxygen: list(markdown = TRUE)
-LazyData: true
-Imports:
-  S7,
-  tools,
-  httr2, 
-  stats
-Suggests: 
-    testthat (>= 3.0.0)
-Config/testthat/edition: 3
-Depends: 
-    R (>= 4.3)
-Config/roxygen2/version: 8.0.0
+Package: PallasExplorer
+Type: Package
+Title: Sparql Graph construction and object Auto-suggestion 
+Version: 0.0.0.9000
+Authors@R: c(
+    person(
+      "Ata", "Badr Barzegar",
+      email = "atabadrbarzegar@gmail.com",
+      role = c("aut", "cre")
+    )
+  )
+Description: The main goal is to connect to SPARQL endpoints and bering their structure into the R world. This package would enable R developers to make a graph of RDF schemas in different endpoints and also access classes and properties with auto-suggestion mechanism enabled in R.  
+License: MIT + file LICENSE
+Encoding: UTF-8
+Roxygen: list(markdown = TRUE)
+LazyData: true
+Imports:
+  S7,
+  tools,
+  httr2, 
+  stats
+Suggests: 
+    testthat (>= 3.0.0), 
+    withr
+Config/testthat/edition: 3
+Depends: 
+    R (>= 4.3)
+Config/roxygen2/version: 8.0.0
diff --git a/tests/testthat/test-cache.R b/tests/testthat/test-cache.R
index e0a2b78..87f2a17 100644
--- a/tests/testthat/test-cache.R
+++ b/tests/testthat/test-cache.R
@@ -1,6 +1,24 @@
 test_that("pallas_graph_cache_dir returns an existing directory", {
-  dir <- pallas_graph_cache_dir()
+  dir <- pallas_graph_cache_dir("PallasTestDefault")
+  withr::defer(unlink(dir, recursive = TRUE))
 
   expect_type(dir, "character")
   expect_true(dir.exists(dir))
 })
+
+test_that("pallas_graph_cache_dir respects a custom dir_name", {
+  dir <- pallas_graph_cache_dir("PallasTestCustom")
+  withr::defer(unlink(dir, recursive = TRUE))
+
+  expect_true(grepl("PallasTestCustom", dir, fixed = TRUE))
+})
+
+test_that("pallas_graph_cache_dir is idempotent", {
+  dir1 <- pallas_graph_cache_dir("PallasTestIdempotent")
+  withr::defer(unlink(dir1, recursive = TRUE))
+
+  dir2 <- pallas_graph_cache_dir("PallasTestIdempotent")
+
+  expect_equal(dir1, dir2)
+  expect_true(dir.exists(dir2))
+})
diff --git a/tests/testthat/test-endpoint_class.R b/tests/testthat/test-endpoint_class.R
index fdc8877..53ce144 100644
--- a/tests/testthat/test-endpoint_class.R
+++ b/tests/testthat/test-endpoint_class.R
@@ -1,4 +1,63 @@
-test_that("sparql_endpoint validator rejects a bad url", {
-  expect_error(sparql_endpoint(url = ""))
-  expect_error(sparql_endpoint(url = c("a", "b")))
+test_that("sparql_endpoint stores valid custom property values", {
+  example_url <- "https://example.org/sparql"
+  example_name <- "example"
+  example_headers <- list(Accept = "application/json")
+  example_timeout <- 30
+
+  ep <- sparql_endpoint(
+    url = example_url,
+    name = example_name,
+    headers = example_headers,
+    timeout = example_timeout
+  )
+
+  expect_equal(ep@url, example_url)
+  expect_equal(ep@name, example_name)
+  expect_equal(ep@headers, example_headers)
+  expect_equal(ep@timeout, example_timeout)
+})
+
+test_that("sparql_endpoint has the right defaults", {
+  ep <- sparql_endpoint(url = "https://example.org/sparql")
+
+  expect_true(is.na(ep@name))
+  expect_equal(ep@headers, list())
+  expect_equal(ep@timeout, 60)
+})
+
+test_that("sparql_endpoint@url validator rejects bad values", {
+  expect_error(sparql_endpoint(url = ""), regexp = "non-empty")
+  expect_error(sparql_endpoint(url = c("a", "b")), regexp = "single")
+})
+
+test_that("sparql_endpoint@name validator rejects non-scalar values", {
+  expect_error(
+    sparql_endpoint(url = "https://example.org", name = c("a", "b")),
+    regexp = "single"
+  )
+})
+
+test_that("sparql_endpoint@headers validator rejects unnamed lists", {
+  expect_error(
+    sparql_endpoint(url = "https://example.org", headers = list("application/json")),
+    regexp = "named"
+  )
+  expect_error(
+    sparql_endpoint(url = "https://example.org", headers = list(Accept = "a", "b")),
+    regexp = "named"
+  )
+})
+
+test_that("sparql_endpoint@timeout validator rejects non-positive or NA values", {
+  expect_error(sparql_endpoint(url = "https://example.org", timeout = 0), regexp = "positive")
+  expect_error(sparql_endpoint(url = "https://example.org", timeout = -5), regexp = "positive")
+  expect_error(sparql_endpoint(url = "https://example.org", timeout = NA_real_), regexp = "positive")
+  expect_error(sparql_endpoint(url = "https://example.org", timeout = c(1, 2)), regexp = "positive")
+})
+
+test_that("generic_endpoint inherits from sparql_endpoint", {
+  ep <- generic_endpoint(url = "https://example.org/sparql")
+
+  expect_true(S7::S7_inherits(ep, generic_endpoint))
+  expect_true(S7::S7_inherits(ep, sparql_endpoint))
 })