If you are integrating with XERO, then the Xero API previewer is a fantastic tool to quickly check query formats, data formats and data values as well. It returns real data from the account you logged in as and you can even copy and paste the results handraulically into another system for processing. The only issue is that it is quite hard to read.
Where the contents show:
f483dea8-6a1f-426b-be3c-17b4a38a8653
OK
Xero API Previewer
2013-08-27T08:33:43.3599219Z
4b3c8980-cc25-45a5-8821-91af40ef1ab1
TestTo
2013-06-30T00:00:00
AUTHORISED
Inclusive
31000.00
0.00
31000.00
2013-06-30T03:05:13.253
USD
1a848561-0fef-4872-88c1-0c9998e6720a
edb716d5-001b-4a10-92a1-cbaaca4e0970
Test1
SPEND
TestRef
false
false
cb3e4439-fbf0-4a5b-84e3-3b3dfb531f28
SpendTo
2013-06-30T00:00:00
AUTHORISED
Inclusive
40000.00
0.00
40000.00
2013-06-30T03:09:27.897
USD
6961882c-141a-4caa-bf47-6db51b718fd7
edb716d5-001b-4a10-92a1-cbaaca4e0970
Test1
SPEND
SpendRef
false
false
7b4acc9b-4fe3-4cce-9ef6-713838d0250e
Test3
2013-06-30T00:00:00
AUTHORISED
Inclusive
130235.00
0.00
130235.00
2013-06-30T06:28:19.537
USD
d54bf964-5366-4118-ab97-4b1b82a7b183
a4865cca-73f0-4da6-8bb4-e9e2a5fd7fda
AccountNameCC
SPEND
CCSpentRef
false
false
067dd16c-d080-499c-b82b-843b71ae8e24
AccountCCTo1
2013-07-01T00:00:00
AUTHORISED
Inclusive
101.00
0.00
101.00
2013-07-01T02:31:35.127
USD
278b63c3-e656-4624-bf3b-154b97619afe
4aee2adf-f64b-4299-9561-5cf899536325
AccountCreditcard1
SPEND
AccountCCTo1Ref
false
false
cca1d8f6-4d0d-4a3d-aaa2-634254c80a9d
John
2013-08-15T00:00:00
AUTHORISED
Inclusive
40000.00
0.00
40000.00
2013-08-14T22:08:23.427
USD
d039fe9f-a2d7-4f9a-9ada-257a63a12557
a4865cca-73f0-4da6-8bb4-e9e2a5fd7fda
AccountNameCC
RECEIVE
false
false
4b3c8980-cc25-45a5-8821-91af40ef1ab1
TestTo
2013-08-04T00:00:00
AUTHORISED
NoTax
10800.00
0.00
10800.00
2013-08-15T05:46:00.557
USD
6ffb0bb1-f842-4b93-bae8-6c15af7681b6
0139cefc-944b-4d16-8070-fc45d4a0f774
Saving Account
SPEND-OVERPAYMENT
false
false
80c98f3f-27fa-4cee-907b-07a1a748247e
Test/Test1
2013-08-15T00:00:00
AUTHORISED
Inclusive
30000.00
0.00
30000.00
2013-08-18T03:05:06.42
USD
a37dc5ae-c0b1-484c-b248-8b641fb37483
edb716d5-001b-4a10-92a1-cbaaca4e0970
Test1
RECEIVE
false
false
2013-06-30T00:00:00
DELETED
NoTax
12.00
2013-08-18T03:05:48.743
USD
4d6ccd40-8772-4518-b221-08e2125abd51
edb716d5-001b-4a10-92a1-cbaaca4e0970
Test1
SPEND-TRANSFER
false
false
2013-06-30T00:00:00
DELETED
NoTax
12.00
2013-08-18T03:05:48.743
USD
65b712a4-1092-4bc5-8f43-aa16d27efc99
0139cefc-944b-4d16-8070-fc45d4a0f774
Saving Account
RECEIVE-TRANSFER
false
false
fac19df4-e92b-45d1-9565-115933a65481
Paul
2013-08-18T00:00:00
AUTHORISED
Inclusive
22000000.00
0.00
22000000.00
2013-08-18T03:07:53.343
USD
ebbd4239-385e-48e7-b40e-c930a263b33e
0139cefc-944b-4d16-8070-fc45d4a0f774
Saving Account
RECEIVE
false
false
9b8d7fd5-9e81-4dcd-949b-c5236128d147
My Test
2013-08-17T00:00:00
AUTHORISED
Inclusive
20000000.00
0.00
20000000.00
2013-08-18T03:12:32.013
USD
9484a732-2ae7-44a8-af86-4e111710cdac
0139cefc-944b-4d16-8070-fc45d4a0f774
Saving Account
RECEIVE
false
false
The trick is to copy this into notepad and save it as an XML file. Then use excel to import this XML file.

