CLI-first TurboTable-style calculations for contact-center planning.
mod_turbotab keeps the historical name known by call-center planning and traffic analysts, while exposing turbotab as the primary interface for humans, scripts, and AI agents.
turbotab staffing required --sla 0.80 --service-time 20 --calls-per-interval 25 --aht 180 --json
{"calculation": "staffing.required", "inputs": {"aht": 180, "calls_per_interval": 25.0, "interval": 600.0, "service_time": 20, "sla": 0.8}, "result": {"name": "agents", "unit": "agents", "value": 11}, "schema_version": "1.0"}
Why
mod_turbotab answers operational questions that show up constantly in contact-center planning:
| Question | Command |
|---|---|
| How many agents do I need? | turbotab staffing required ... |
| What SLA will this staffing achieve? | turbotab sla achieved ... |
| How long will the queue wait be? | turbotab queue wait ... |
| How many trunks are required? | turbotab telecom trunks ... |
| What is the Erlang B/C/A result? | turbotab erlang ... |
It provides Erlang B, extended Erlang B, Engset B, Erlang C, Erlang A, queue metrics, staffing metrics, call capacity, and telephony trunk sizing with no third-party runtime dependencies.
Quick Start
Required staffing for 80% SLA in 20 seconds:
turbotab staffing required \
--sla 0.80 \
--service-time 20 \
--calls-per-interval 25 \
--aht 180 \
--json
Achieved SLA for a fixed staffing level:
turbotab sla achieved \
--agents 11 \
--service-time 20 \
--calls-per-interval 25 \
--aht 180 \
--json
Average queue wait:
turbotab queue wait \
--agents 11 \
--calls-per-interval 25 \
--aht 180 \
--json
Required trunks:
turbotab telecom trunks \
--agents 11 \
--calls-per-interval 25 \
--aht 180 \
--json
Every command group falls back to contextual help:
turbotab
turbotab sla
turbotab staffing required --help
CLI
Agent-facing commands are intent-first:
turbotab
├── staffing
│ ├── required
│ ├── asa
│ ├── capacity
│ ├── fractional-required
│ └── fractional-capacity
├── sla
│ ├── achieved
│ └── target-time
├── queue
│ ├── wait
│ ├── size
│ └── probability
└── telecom
└── trunks
Detailed formula/module commands are also available:
turbotab agents ...
turbotab queues ...
turbotab erlang ...
turbotab traffic ...
turbotab trunks ...
Use --json when calling from agents or automation. Invalid inputs exit non-zero and print a concise error to stderr.
Agent usage
Agents should prefer the CLI with --json instead of parsing text output or importing Python internals.
turbotab staffing required --sla 0.80 --service-time 20 --calls-per-interval 25 --aht 180 --json
JSON output is the stable agent contract:
{
"schema_version": "1.0",
"calculation": "staffing.required",
"inputs": {
"aht": 180,
"calls_per_interval": 25.0,
"interval": 600.0,
"service_time": 20,
"sla": 0.8
},
"result": {
"name": "agents",
"unit": "agents",
"value": 11
}
}
The bundled skill lives at skills/mod-turbotab/SKILL.md. It includes command recipes, unit rules, and agent guardrails.
Units and assumptions
This project uses interval-based planning buckets.
Every function or CLI command that accepts call volume uses calls_per_interval, not calls per hour by default.
| Parameter | Meaning |
|---|---|
calls_per_interval / --calls-per-interval |
Arrivals in the planning bucket |
interval / --interval |
Planning bucket in seconds |
Default interval |
600 seconds, or 10 minutes |
aht / --aht |
Average handle time in seconds |
service_time / --service-time |
Target answer time in seconds |
sla / --sla |
Ratio, for example 0.80 for 80% |
For hourly semantics, pass --interval 3600:
turbotab staffing required --sla 0.80 --service-time 20 --calls-per-interval 150 --aht 180 --interval 3600 --json
Traffic intensity is computed as:
A = \frac{\lambda \cdot h}{I}
where A is offered traffic in erlangs, lambda is arrivals per interval, h is AHT in seconds, and I is interval length in seconds.
Worked example
With the default 10-minute bucket:
| Input | Value |
|---|---|
| Calls | 25 per 10 minutes |
| AHT | 180 seconds |
| Target SLA | 0.80 |
| Target answer time | 20 seconds |
CLI:
turbotab staffing required --sla 0.80 --service-time 20 --calls-per-interval 25 --aht 180 --json
turbotab sla achieved --agents 11 --service-time 20 --calls-per-interval 25 --aht 180 --json
turbotab queue wait --agents 11 --calls-per-interval 25 --aht 180 --json
turbotab telecom trunks --agents 11 --calls-per-interval 25 --aht 180 --json
Expected headline results:
| Metric | Result |
|---|---|
| Required agents | 11 |
| Achieved SLA | 0.880836 |
| Average queue wait | 51 seconds |
| Required trunks | 18 |
Python API equivalent:
from mod_turbotab.agents.capacity import agents_required
print(agents_required(0.80, 20, 25, 180))
Mathematical model
Notation:
| Symbol | Meaning |
|---|---|
N |
Agents, servers, or trunks depending on context |
lambda |
Arrival volume per configured interval |
h |
Average handle time in seconds |
I |
Planning interval in seconds |
mu |
Service completions per interval per server |
A |
Offered traffic in erlangs |
rho |
Utilization |
B(N, A) |
Erlang B blocking probability |
C(N, A) |
Erlang C queueing probability |
Core conversions:
\mu = \frac{I}{h}
A = \frac{\lambda}{\mu} = \frac{\lambda h}{I}
\rho = \frac{A}{N}
Erlang B recurrence:
B_0 = 1
B_n = \frac{A B_{n-1}}{n + A B_{n-1}}
Erlang C:
C(N, A) = \frac{B(N, A)}{\left(\frac{A}{N}\right) B(N, A) + \left(1 - \frac{A}{N}\right)}
Queue wait:
W_q = \frac{1}{N \mu (1 - \rho)}
SLA:
\mathrm{SLA}(t) = 1 - C(N, A)\exp\left(-\frac{N - A}{h}t\right)
ASA:
\mathrm{ASA} = \frac{C(N, A)}{N \mu (1 - \rho)}
Erlang A extends Erlang C with abandonment through average patience. When patience=None, pure Erlang C is used.
API reference
The CLI is the primary interface, but the Python API remains available.
| Module | Public functions |
|---|---|
calculations.erlang |
erlang_b, erlang_b_ext, engset_b, erlang_c, erlang_a |
calculations.traffic |
traffic, looping_traffic |
agents.capacity |
agents_required, asa, agents_asa, nb_agents, call_capacity, fractional_agents, fractional_call_capacity |
queues.queues |
queued, queue_size, queue_time, service_time, sla_metric |
trunks.trunks |
number_trunks, trunks_required |
utils |
min_max, int_ceiling, secs |
Import example:
from mod_turbotab.agents.capacity import agents_required
agents = agents_required(
sla=0.80,
service_time=20,
calls_per_interval=25,
aht=180,
)
Exceptions
Project-specific exceptions live in exceptions.py:
| Exception | Meaning |
|---|---|
InputValidationError |
Invalid argument values |
CalculationError |
Calculation failed or search could not converge |
Example:
from mod_turbotab.exceptions import CalculationError, InputValidationError
try:
...
except InputValidationError:
...
except CalculationError:
...
Limitations
number_trunks()uses a fixed blocking threshold of0.001.- Some zero-value edge cases still return wrapped calculation errors instead of purpose-built validation messages.
- Shrinkage, absenteeism, occupancy caps, and intraday simulation are tracked as future work in
coming_soon/.
Metadata
Release files for mod-turbotab 0.1.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
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|---|---|---|---|---|
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Total release size: 99.4 kB
Release files / mod_turbotab-0.1.0.tar.gz
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| Tags | Source |
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