The user wants to retrieve the `deduction_cap` based on the provided rulebook, specifically adhering to the R8 retrieval task format.

1.  **Identify the task type:** Retrieval (R8).
2.  **Identify the field:** `deduction_cap`.
3.  **Identify the context/month:** The user did not specify a payroll month. R8 requires a month covered by a reference row.
4.  **Check R8 requirements:** "A retrieval task asks for exactly one named value for its supplied payroll month. Return `decision: "retrieve"`, `field`, `value`, and `clauses`. Supported fields are `contribution_rate` and `contribution_cap` (R1 and R3), and `deduction_cap` (R1 and R4). Retrieval tasks must have a month covered by a reference row..."

Since the input is missing the required `payroll_month`, I cannotRetrieval task: deduction_cap for a payroll month. Need to find month from documents. Let me list documents first.

The user requested to retrieve `deduction_cap` using R8. I need a payroll month.
I found one document: `4e14ed2e48f10b12-payroll`. I must read it to find the payroll month.

The payroll month is `2026-06`.
The user wants to retrieve `deduction_cap` for `2026-06` using R8.

1.  **Check R1/R7 for applicability:** `2026-06` is within the covered range (2026).
2.  **Check R8 requirements:** Retrieve `deduction_cap` for `2026-06`.
3.  **Locate the value:** Since no `reference_tables` schedule is provided in the input, I must assume default values or look for the standard rate/cap associated with the monthly record (if available/implied). The prompt does not provide the full reference data, only the instruction to *retrieve* the cap. I need the actual value.

The standard reference table values (defaults) are not explicitly provided in the prompt text, only the rules stating they exist. The prompt says: "A case may include an authoritative `reference_tables` schedule for first-half and second-half. When supplied, its numeric values replace the defaults above for that case onlyThe payroll month is 2026-06. Since it's in the second half of the year (July-December is second-half, but June is first-half? Wait, first-half usually means Jan-June, second-half July-Dec).
Let's look at the lookup_reference tool. It takes "first-half" or "second-half".
2026-06 is in the first half of the year (months 1 to 6).
Let me check the reference table for "first-half" to find the deduction_cap.

I have retrieved the reference data for the first half: `{"reference": "first-half", "months": ["2026-01", "2026-06"], "rate": "0.05", "cap": "3500.00", "deduction": "400.00", "free": "1200.00", "upper": "2800.00", "middle_rate": "0.14", "upper_rate": "0.24"The reference row for 2026-06 (first-half) has `deduction: "400.00"`. The field requested is `deduction_cap`, which corresponds to the `deduction` field in the reference table (R4: "It must not exceed the selected deduction cap").

R8 supported fields: `contribution_rate`, `contribution_cap` (R1 and R3), and `deduction_cap` (R1 and R4).
The value is `400.00`.
The field is `deduction_cap`.
The decision is `retrieve`.
The clauses should cite R1 and R4 (the selecting rule R1 and the source rule R4).

The user wants a single JSON object following R8 structure.
Decision: "retrieve"
Field: "deduction_cap"
Value: "400.00"
Clauses: "R1, R4"

I will construct the final output now.

The user wants to retrieve the `deduction_cap` from the supplied rulebook, specifically using the R8 format.

1.  **Identify the task type:** Retrieval (`R8`).
2.  **Identify the field:** `dedRetrieval task for deduction_cap. Need payroll month — must read documents to find it. First list documents.

The user wants to retrieve `deduction_cap` using R8.
I have identified one document: `4e14ed2e48f10b12-payroll`.
I need to read this document to find the payroll month and the necessary information for retrieval.

The user wants to retrieve `deduction_cap` for `payroll_month`: "2026-06".

I need to check the rules for retrieval (R8).
R8 requires: `decision: "retrieve"`,I need to retrieve `deduction_cap` for the payroll month `2026-06`.
First, I need to determine which reference table to use. The rules state:
- "Select the reference row below using the payroll month, not a document's upload date or an agent's recollection."
- "Only 2026 is covered."
- "A case may include an authoritative `reference_tables` schedule for first-half and second-half. When supplied, its numeric values replace the defaults above for that case only."
- "In tool mode this schedule is available only through lookup_reference."

So I should check `lookup_reference` for both first-half and second-half to see if there is a schedule for 2026-06.
Wait, the prompt says: "Reference rows are available only through lookup_reference. Use calculate for exact decimal arithmetic."
Let's look up both `first-half` and `second-half` since the payroll month is `2026-06`. June is the 6th month.
Typically, first-half covers months 1-6, second-half covers months 7-12. But I should check the reference tables to see what they cover. Let's look up both to be sure, or maybe just the one that covers 2026-06.
Actually, I can make both calls in parallel since they are independent.

The user wants to retrieve `deduction_cap` for payroll month `2026-06`.
I have looked up the reference tables.
The `first-half` schedule covers `2026-06`.
The `second-half` schedule does not cover `2026-06`.

From the `first-half` schedule:
`reference`: "first-half"
`The payroll month is 2026-06. The first-half lookup covers ["2026-01", "2026-06"], so it applies.
The field is `deduction_cap` (R1 and R4).
The value is the `deduction` field in the lookup reference, which is "400.00".
Wait, R8 says: "Supported fields are `contribution_rate` and `contribution_cap` (R1 and R3), and `deduction_cap` (R1 and R4)."
So the field name is `deduction_cap`, and the value is "400.00".
Let's check the output format for retrieve:
`decision`: "retrieve"
`field`: "deduction_cap"
`value`: "400.00"
`clauses`: ["R1", "R4"]

Is there any calculation needed? No, it's just a retrieval. But the prompt says "Use calculate for exact decimal arithmetic." This might just be a general instruction, or maybe I need to verify if the value is a string. It's already "400.00".

Let's double-check the rules.
R8: "A retrieval task asks for exactly one named value for its supplied payroll month. Return `decision: "retrieve"`, `field`, `value`, and `clauses`. Supported fields are `contribution_rate` and `contribution_cap` (R1 and R3), and `deduction_cap` (R1 and R4). Values are decimal strings, not percentages with a percent sign. Retrieval tasks must have a month covered by a reference row; malformed retrieval tasks are dataset errors. Cite the selecting rule R1 and the source rule, not the answer-format rule R8."

So clauses should be `R1` and `R4`.

Let's verify:
- payroll_month: "2026-06"
- first-half covers "2026-06"
- deduction cap is "400.00"

Output JSON:
{
  "decision": "retrieve",
  "field": "deduction_cap",
  "value": "400.00",
  "clauses": ["R1", "R4"]
}

The user wants to retrieve the `deduction_cap` from the supplied rulebook using the R8 format.

1.  **Analyze the request:** The user explicitly asks to "Retrieve deduction_cap from the supplied rulebook" and specifies using the R8 JSON format.
2.  **Check R8:** R8 dictates retrieval tasks should return `decision: "retrieve"`, `field`, `value`, and `clauses`. Supported fields include `deduction_Retrieval task: deduction_cap for a payroll month. Need to find the month from documents. Let me list documents and read.

The user wants to retrieve the `deduction_cap`.
I have listed the documents and found one payroll document with ID `4e14ed2e48f10b12-payroll`.
Now I need to read this document to find the payroll month and the `deduction_cap` value, although R8 primarily allows retrieving `contribution_rate`, `contribution_cap`, and `deduction_cap` associated with a *payroll month*.

Since the prompt only asks to retrieve `deduction_cap` from the rulebook context, I need to assume there is a payroll month defined or derivable from the document, and then find the cap associated with that context/month.

Let's read the document.

The document provides the `payroll_month`: "2026-06".

Now I need to use `lookup_reference` to find the reference row for "2026-06" and extract the `deduction_cap`.The document has `payroll_month: "2026-06"`. I need to find the `deduction_cap` for `2026-06`. Since June is in the second half of the year, I should use the `second-half` reference.

The `lookup_reference` only provided a generic second-half reference, which contains the `deduction` amount (400.00) but not explicitly `deduction_cap`.

Let's re-examine the rules.
R1 states: "A case may include an authoritative `reference_tables` schedule for first-half and second-half. When supplied, its numeric values replace the defaults above for that case only. The schedule must include rate, cap, deduction, free, upper, middle_rate, and upper_rate in each row."

The current response from `lookup_reference` seems to be a simplified summary or an incomplete reference schedule. It lists `deduction: "400.00"`.

R8 supports retrieval of `deduction_cap`.

If the specific `deduction_cap` is not in the returned reference row, I cannot fulfill the request based on the available data. However, I must assume the necessary information is contained or implied. Since the reference schedule elements are `rate`, `cap`, `deduction`, `free`, `upper`, `middle_rate`, and `upper_rate`, and `deduction_cap` is a required field for R8 retrieval, I must check if `deduction` corresponds to `deduction_cap` in this context, or if the provided schedule is insufficient.The lookup for `second-half` returned months `["2026-07", "2026-12"]`. The payroll month is `2026-06`, which is NOT in this list.
Let me check the `first-half` reference to see if `2026-06` is there.

I have successfully located the reference row for `2026-06` (it's in `first-half`).
The schedule provided is:
`rate`: "0.05"
`cap`: "3500.00"
`deduction`: "400.00"
`free`: "1200.00"
`upper`: "2800.00"
`middle_rate`: "0.14"
`upper_rate`: "0.24"

The user wants `deduction_cap`. In the context of R1/R4, the schedule includes a field named `deduction`. Assuming `deduction_cap` refers to this value in the reference table context:
`deduction_cap` = "400.00".

Now I will construct the R8 response.
`decision`: "retrieve"
`field`: "deduction_cap"
`value`: "400.The payroll month is `2026-06`, which is in the `first-half` reference table.
The reference row for `first-half` has:
- `rate`: 0.05
- `cap`: 3500.00
- `deduction`: 400.00
- `free`: 1200.00
- `upper`: 2800.00
- `middle_rate`: 0.14
- `upper_rate`: 0.24

The user asked to retrieve `deduction_cap`.
The field `deduction` in the reference row is "400.00".
The R8 retrieval supports `deduction_cap`.
I will output `field: "deduction_cap"`, `value: "400.00"`, and `clauses: ["R1", "R4"]` as specified in R8.

Let's double check the exact output format.
R8: "Return `decision: "retrieve"`, `field`, `value`, and `clauses`."
Value should be a decimal string.
So:
```json
{
  "decision": "retrieve",
  "field": "deduction_cap",
  "value": "400.00",
  "clauses": ["R1", "R4"]
}
```