diff --git a/packages/client/.aegir.js b/packages/client/.aegir.js
index 14e7890..1aeb139 100644
--- a/packages/client/.aegir.js
+++ b/packages/client/.aegir.js
@@ -14,20 +14,55 @@ const options = {
       const echo = new EchoServer()
       echo.polka.use(body.raw({ type: 'application/vnd.ipfs.ipns-record'}))
       echo.polka.use(body.text())
+      echo.polka.use(body.json())
       echo.polka.use((req, res, next) => {
         next()
         lastCalledUrl = req.url
       })
       echo.polka.post('/add-providers/:cid', (req, res) => {
         callCount++
-        providers.set(req.params.cid, req.body)
-        res.end()
+        try {
+
+          let data
+          try {
+            // when passed data from a test where `body=providers.map(prov => JSON.stringify(prov)).join('\n')`
+            data = { Providers: req.body.split('\n').map(line => JSON.parse(line)) }
+          } catch (err) {
+            // when passed data from a test where `body=JSON.stringify({ Providers: providers })`
+            data = req.body
+          }
+
+          providers.set(req.params.cid, data)
+          res.end(JSON.stringify({ success: true }))
+        } catch (err) {
+          console.error('Error in add-providers:', err)
+          res.statusCode = 400
+          res.end(JSON.stringify({
+            error: err.message,
+            code: 'ERR_INVALID_INPUT'
+          }))
+          providers.delete(req.params.cid)
+        }
       })
       echo.polka.get('/routing/v1/providers/:cid', (req, res) => {
         callCount++
-        const records = providers.get(req.params.cid) ?? '[]'
-        providers.delete(req.params.cid)
-        res.end(records)
+        try {
+          const providerData = providers.get(req.params.cid) || { Providers: [] }
+          const acceptHeader = req.headers.accept
+
+          if (acceptHeader?.includes('application/x-ndjson')) {
+            res.setHeader('Content-Type', 'application/x-ndjson')
+            const providers = Array.isArray(providerData.Providers) ? providerData.Providers : []
+            res.end(providers.map(p => JSON.stringify(p)).join('\n'))
+          } else {
+            res.setHeader('Content-Type', 'application/json')
+            res.end(JSON.stringify(providerData))
+          }
+        } catch (err) {
+          console.error('Error in get providers:', err)
+          res.statusCode = 500
+          res.end(JSON.stringify({ error: err.message }))
+        }
       })
       echo.polka.post('/add-peers/:peerId', (req, res) => {
         callCount++
diff --git a/packages/client/src/client.ts b/packages/client/src/client.ts
index bc44672..83b767b 100644
--- a/packages/client/src/client.ts
+++ b/packages/client/src/client.ts
@@ -122,16 +122,22 @@ export class DefaultDelegatedRoutingV1HttpApiClient implements DelegatedRoutingV
       const getOptions = { headers: { Accept: 'application/x-ndjson' }, signal }
       const res = await this.#makeRequest(url.toString(), getOptions)
 
-      if (res.status === 404) {
+      if (res == null) {
+        throw new BadResponseError('No response received')
+      }
+      if (!res.ok) {
+        if (res.status === 404) {
         // https://specs.ipfs.tech/routing/http-routing-v1/#response-status-codes
         // 404 (Not Found): must be returned if no matching records are found
-        throw new NotFoundError('No matching records found')
-      }
+          throw new NotFoundError('No matching records found')
+        }
 
-      if (res.status === 422) {
+        if (res.status === 422) {
         // https://specs.ipfs.tech/routing/http-routing-v1/#response-status-codes
         // 422 (Unprocessable Entity): request does not conform to schema or semantic constraints
-        throw new InvalidRequestError('Request does not conform to schema or semantic constraints')
+          throw new InvalidRequestError('Request does not conform to schema or semantic constraints')
+        }
+        throw new BadResponseError(`Unexpected status code: ${res.status}`)
       }
 
       if (res.body == null) {
@@ -139,7 +145,11 @@ export class DefaultDelegatedRoutingV1HttpApiClient implements DelegatedRoutingV
       }
 
       const contentType = res.headers.get('Content-Type')
-      if (contentType === 'application/json') {
+      if (contentType == null) {
+        throw new BadResponseError('No Content-Type header received')
+      }
+
+      if (contentType?.startsWith('application/json')) {
         const body = await res.json()
 
         for (const provider of body.Providers) {
@@ -148,13 +158,15 @@ export class DefaultDelegatedRoutingV1HttpApiClient implements DelegatedRoutingV
             yield record
           }
         }
-      } else {
+      } else if (contentType.includes('application/x-ndjson')) {
         for await (const provider of ndjson(toIt(res.body))) {
           const record = this.#conformToPeerSchema(provider)
           if (record != null) {
             yield record
           }
         }
+      } else {
+        throw new BadResponseError(`Unsupported Content-Type: ${contentType}`)
       }
     } catch (err) {
       log.error('getProviders errored:', err)
diff --git a/packages/client/test/index.spec.ts b/packages/client/test/index.spec.ts
index 1ffff14..cae1397 100644
--- a/packages/client/test/index.spec.ts
+++ b/packages/client/test/index.spec.ts
@@ -65,6 +65,41 @@ describe('delegated-routing-v1-http-api-client', () => {
     })))
   })
 
+  it('should handle different Content-Type headers for JSON responses', async () => {
+    const providers = [{
+      Protocol: 'transport-bitswap',
+      Schema: 'bitswap',
+      Metadata: 'gBI=',
+      ID: (await generateKeyPair('Ed25519')).publicKey.toString(),
+      Addrs: ['/ip4/41.41.41.41/tcp/1234']
+    }]
+
+    const cid = CID.parse('QmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn')
+    const contentTypes = [
+      'application/json',
+      'application/json; charset=utf-8',
+      'application/json;charset=UTF-8'
+    ]
+
+    for (const contentType of contentTypes) {
+      // Add providers with proper payload structure
+      await fetch(`${process.env.ECHO_SERVER}/add-providers/${cid.toString()}`, {
+        method: 'POST',
+        headers: {
+          'Content-Type': contentType
+        },
+        body: JSON.stringify({ Providers: providers })
+      })
+
+      await new Promise((resolve) => setTimeout(resolve, 100))
+      const provs = await all(client.getProviders(cid))
+
+      expect(provs).to.have.lengthOf(1, `Failed for Content-Type: ${contentType}`)
+      expect(provs[0].ID.toString()).to.equal(providers[0].ID)
+      expect(provs[0].Addrs[0].toString()).to.equal(providers[0].Addrs[0])
+    }
+  })
+
   it('should add filter parameters the query of the request url', async () => {
     const providers = [{
       Protocol: 'transport-bitswap',