In e na ional Jou nal o Eme ging T ends in Enginee ing and De elopmen Issue 15, Vol.6, 2025
A ailable online on h p://www. spublica ion.com/ije ed/ije ed_index.h m ISSN 2249-6149
DOI: 10.5281/zenodo.17682477
O iginal A icle
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The Rise o Paymen Agen s: A F amewo k o T us , Policy, and Au onomy h ough AP2
Kalyanasundha am Ramachand an
PayPal, US
h ps://o cid.o g/0009-0007-2508-1862
I. I
NTRODUCTION
The shi om s a ic applica ions o au onomous and semi
au onomous agen s is changing how people in e ac wi h
comme ce. Today paymen lows assume a pe son is ac i ely
p esen du ing checkou . The pe son eads disclosu es,
con i ms amoun s, selec s a paymen ins umen , and accep s
e ms. Agen s challenge his model. An agen can scan o e s,
compa e p ices, check wa an ies, e alua e shipping, and
decide o pu chase wi hin milliseconds. I can also plan
ecu ing pu chases, synch onize household budge s, and a gue
abou p oduc subs i u ions when in en o y changes.
This new mode o in e ac ion equi es mo e han a new use
in e ace. I calls o a p o ocol ha allows agen s o exp ess
in en , p o e au ho i y, nego ia e e ms, sa is y policy, and
comple e se lemen . Exis ing p o ocols o he web o
paymen s ocus on message o ma s, anspo secu i y, and
ga eway in eg a ion. They do no de ine how an agen con eys
he scope o delega ed au ho i y, how a me chan e i ies ha
scope, how bo h pa ies ag ee on isk con ols, o how all o i
is eco ded in a way ha can be audi ed la e . AP2 add esses
hese gaps.
We de ine an agen as a so wa e p ocess ha ac s on behal o
a p incipal and can pe cei e inpu s, eason o e policy, and ake
ac ions o each a goal. A p incipal can be a consume , a
me chan , a ma ke place, a inancial ins i u ion, o a egula o .
AP2 gi es each p incipal a clea way o exp ess wha an agen
may do and unde wha condi ions, and i gi es coun e pa ies
a s anda d way o e i y ha exp ession be o e mo ing alue.
In e naonal Jou nal o Eme ging T ends in Enginee ing and
De elopmen
A ailable online on
hp://www. spublicaon.com/ije ed/ije ed_index.h m
ISSN 2249-6149
ARTICLE INFO
ABSTRACT
©2025 RS Publica ion
Pape ID: IJETED-
691409DC03FC6
Recei ed: 2025-10-22
Published: 2025-11-21
DOI:
h ps://dx.doi.o g/1
0.5281/zenodo.176824
77
Page No: 69-75
Agen so wa e is beginning o ake on complex asks ha once equi ed human ope a o s.
Paymen s a e a na u al place o agen assis ance because paymen in en , iden i y, us , isk,
en i lemen s, and compliance all con e ge a he poin o alue ans e . This pape p oposes
he Agen Paymen s P o ocol, o AP2, a p o ocol o sa e, anspa en , and p og ammable
paymen s ini ia ed and nego ia ed by agen s on behal o people and businesses. AP2 de ines
a laye ed model ha sepa a es iden i y, policy, nego ia ion, and se lemen . I in oduces a
capabili y-based au ho iza ion scheme, a decidable policy language o isk and compliance,
e i iable p oo s o audi , and a anspo ha wo ks ac oss ca d, accoun o accoun , and
walle ne wo ks. We p esen an a chi ec u e, implemen a ion s a egies, and a conc e e
discussion o how AP2 can bene i consume s and me chan s. We close wi h open esea ch
ques ions and a oadmap o u u e wo k.
Keywo ds --- Paymen p ocessing, Ne wo k okeniza ion, F aud mi iga ion, PCI okeniza ion,
Regula o y compliance, Cybe secu i y, S akeholde s, Financial ins i u ions, Paymen se ice
p o ide s, Cha geback managemen , Au hen ica ion mechanisms
Ci e This Pape : Kalyanasundha am Ramachand an (2025). "The Rise o Paymen
Agen s: A F amewo k o T us , Policy, and Au onomy h ough AP2".
INTERNATIONAL JOURNAL OF EMERGING TRENDS IN ENGINEERING AND
DEVELOPMENT (IJETED), ol. 15, no. 6, 2025, pp. 69-75. DOI:
h ps://dx.doi.o g/10.5281/zenodo.17682477
In e na ional Jou nal o Eme ging T ends in Enginee ing and De elopmen Issue 15, Vol.6, 2025
A ailable online on h p://www. spublica ion.com/ije ed/ije ed_index.h m ISSN 2249-6149
DOI: 10.5281/zenodo.17682477
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II. PROBLEM
STATEMENT
The cu en digi al paymen ecosys em is buil upon p o ocols
and in as uc u es ha assume human pa icipa ion and di ec
in e ac ion a he poin o ansac ion. T adi ional sys ems such
as ca d-based ne wo ks, accoun - o-accoun ans e s, and
digi al walle s ely on s a ic au ho iza ion models, manual
e i ica ion s eps, and ixed policy en o cemen mechanisms.
While hese sys ems ha e e ol ed o handle scale and secu i y,
hey a e no designed o a wo ld whe e au onomous agen s ac
on behal o use s o o ganiza ions [1]. The absence o a
s anda dized p o ocol o agen -media ed paymen s c ea es
signi ican challenges ac oss in e ope abili y, isk managemen ,
and compliance.
Fi s , he e is no uni e sally accep ed mechanism o delega ing
inancial au ho i y o so wa e agen s in a e i iable and
e ocable manne . This gap leads o agmen ed
implemen a ions and bespoke in eg a ions ha comp omise
bo h secu i y and use us . Second, policy en o cemen o
isk, aud, and compliance emains igid, equi ing human
o e sigh and slowing down ansac ions ha could o he wise
be au oma ed sa ely h ough e i iable logic and p oo s. Thi d,
in e ope abili y ac oss mul iple paymen ails and ju isdic ions
is limi ed, as each ne wo k ope a es unde i s own se o
assump ions abou iden i y, au ho iza ion, and consen . As a
esul , agen -d i en ansac ions canno low seamlessly ac oss
sys ems o bo de s.
Fu he mo e, he exis ing paymen amewo ks do no p o ide
a s uc u ed means o nego ia ion be ween agen s. T adi ional
sys ems suppo only s a ic p ice and policy pa ame e s, while
agen s equi e dynamic nego ia ion capabili ies o e alua e and
op imize o e s based on con ex , p ice, incen i es, and
compliance cons ain s. This lack o nego ia ion seman ics
p e en s he eme gence o au onomous comme ce, whe e
agen s could e icien ly ma ch in en s and o e s wi hou
manual in e en ion.
The inabili y o ep esen and p o e policy compliance in a
p i acy-p ese ing way is ano he ba ie . As agen s handle
sensi i e pe sonal and inancial da a, hey need o demons a e
eligibili y and au ho iza ion wi hou exposing mo e in o ma ion
han necessa y [2]. Cu en sys ems expose da a beyond wha is
equi ed o e i ica ion, c ea ing unnecessa y p i acy isks.
Finally, he absence o audi abili y o au onomous decisions
leads o accoun abili y gaps, as he e is no e i iable chain o
e idence linking an agen ’s ac ion o a speci ic consen o
capabili y g an ed by he p incipal.
The e o e, he e is a p essing need o a uni ied, agen -cen ic
paymen s p o ocol ha enables secu e delega ion, dynamic
nego ia ion, policy-d i en au ho iza ion, and in e ope able
se lemen while main aining anspa ency, audi abili y, and
p i acy. The Agen Paymen s P o ocol (AP2) is p oposed as a
comp ehensi e solu ion o hese p oblems, in oducing a
s anda d amewo k ha can e ol e wi h he ise o au onomous
agen s in comme ce.
III. T
HE NEED FOR AGENTS IN
PAYMENTS
Paymen s a e a mo e complex han simple au ho iza ion and
cap u e. E e y ansac ion is su ounded by laye s o con ex ,
wha is being pu chased, o whom i is in ended, when and
whe e i occu s, and unde wha cons ain s o policies i mus
comply. His o ically, humans ha e managed his con ex
in ui i ely, making nuanced decisions based on pe sonal
judgmen , p io expe iences, and si ua ional awa eness.
Howe e , as comme ce becomes inc easingly digi al and
ins an aneous, his human-cen ic app oach becomes a
bo leneck. Agen s can ex end human capabili y by handling
hese con ex ual elemen s a machine speed and scale.
In he mode n paymen landscape, agen s can play an essen ial
ole in op imizing consume and me chan in e ac ions. They
can con inuously disco e ele an o e s, discoun s, and
incen i es aligned wi h a use ’s speci ic in en , ensu ing ha he
p incipal always bene i s om he bes a ailable e ms. Beyond
me e p ice compa ison, agen s can e alua e mul iple
dimensions o a ansac ion shipping op ions, deli e y
imelines, wa an y condi ions, e u n policies, ax implica ions,
and e en en i onmen al impac o help each decisions ha
align wi h he use ’s goals o alues.
Agen s can also in elligen ly selec he mos app op ia e
paymen ins umen based on eal- ime da a abou a ailable
ewa ds, in e change ees, c edi balances, and me chan
accep ance. They can apply isk managemen s a egies such as
eloci y checks, loca ion-based cons ain s, o spending
ca ego y limi s wi hou equi ing use in e en ion. By
au oma ing hese con ols, agen s can educe aud exposu e
while main aining use con enience.
Ano he a ea whe e agen s p o ide subs an ial alue is in pos -
paymen ac i i ies. They can au oma ically gene a e accu a e
and de ailed expense ca ego iza ions and digi al eceip s,
linking e e y ansac ion o i s pu pose o p ojec o simpli ied
econcilia ion [3]. Agen s can coo dina e complex paymen
scena ios such as sha ed walle s, g oup expenses, and mul i-
In e na ional Jou nal o Eme ging T ends in Enginee ing and De elopmen Issue 15, Vol.6, 2025
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pa y app o als asks ha a e cumbe some and e o -p one
when handled manually.
Equally impo an , agen s can se e as p i acy gua dians. They
can e eal only he da a equi ed o a speci ic ansac ion while
keeping all o he pe sonal o inancial in o ma ion con iden ial.
This selec i e disclosu e capabili y minimizes da a exposu e
and s eng hens use us in digi al ecosys ems.
Wi hou a s anda dized amewo k, howe e , hese capabili ies
isk agmen a ion. Each agen would need o in eg a e
independen ly wi h me chan sys ems, leading o inconsis ency,
secu i y ulne abili ies, and high main enance o e heads. This
mi o s he p e-s anda diza ion e a o paymen s, when bespoke
in eg a ions hinde ed scalabili y and in e ope abili y. The
Agen Paymen s P o ocol (AP2) elimina es hese ine iciencies
by de ining a uni ied s uc u e o messages, p oo s, and
in e ac ion pa e ns ha allow any complian agen o ansac
wi h any complian payee seamlessly, secu ely, and
anspa en ly.
IV. T
HE NEED FOR AN AGENTIC
PROTOCOL FOR PAYMENTS
The in oduc ion o agen s in o he paymen ’s ecosys em
c ea es a undamen al shi in how ansac ions a e concei ed,
ini ia ed, and comple ed. T adi ional paymen sys ems we e
designed a ound di ec use in e ac ion, whe e he cus ome o
me chan igge s each s ep h ough a b owse , poin -o -sale
e minal, o applica ion [4]. In con as , agen -ini ia ed
paymen s in ol e au onomous o semi-au onomous en i ies
ac ing on behal o indi iduals o o ganiza ions, o en in
dynamic and da a-d i en en i onmen s. This pa adigm shi
demands a new class o p o ocol one ha ecognizes he unique
seman ics, esponsibili ies, and e i iabili y equi emen s o
agen ic ansac ions.
A he hea o his new model is he concep o delega ion. In
an agen ic paymen low, a pe son o business delega es
inancial au ho i y o an agen wi hin a clea ly de ined scope.
This delega ion canno be assumed o implici ; i mus be
explici ly exp essed, c yp og aphically bound, and e i iable by
coun e pa ies. Each agen mus p esen e idence o i s
au ho iza ion, including cons ain s on spending limi s,
ca ego ies, du a ion, o me chan ypes. Wi hou such
s uc u ed delega ion, he sys em isks misuse, aud, and
accoun abili y ailu es. The e o e, a p o ocol mus ensu e ha
e e y ac o paymen is aceably linked o he consen and
capabili y g an ed by he p incipal.
Ano he de ining ea u e o agen ic paymen s is explici
nego ia ion. Unlike adi ional sys ems ha ely on s a ic
p icing o p ede ined e ms, agen s a e expec ed o nego ia e
dynamically adjus ing pa ame e s such as p ice, deli e y, ax,
bundling, o isk con ols based on con ex ual in o ma ion. To
suppo his, he p o ocol mus p o ide channels o s uc u ed
nego ia ion, ensu ing ha ag eemen s eached be ween agen s
a e o mally ep esen ed, c yp og aphically signed, and
insepa able om he inal ansac ion. This ans o ms
comme ce in o a p og ammable dialogue be ween in elligen
sys ems, eplacing s a ic o ms wi h adap i e, da a-d i en
exchanges.
P og ammable policy is equally essen ial in his con ex . Agen s
ope a e ac oss di e se ju isdic ions and paymen ne wo ks,
each go e ned by unique egula o y, compliance, and p i acy
amewo ks. A obus agen ic p o ocol mus he e o e embed a
policy laye ha exp esses condi ions o compliance co e ing
iden i y e i ica ion, sanc ions sc eening, ansac ion limi s,
and da a-sha ing cons ain s and suppo s e i iable p oo s o
compliance. These policies should be machine- eadable and
audi able, enabling au oma ic en o cemen wi hou con inuous
human supe ision. In doing so, he p o ocol no only simpli ies
compliance bu also enhances secu i y and us .
T anspa ency becomes a non-nego iable a ibu e in an
en i onmen whe e decisions a e made au onomously. Each
ac ion pe o med by an agen mus be explainable, aceable,
and e-cons uc able. The p o ocol mus eco d wha was
decided, why i was decided, and unde wha au ho i y i was
execu ed. This ensu es accoun abili y and suppo s pos -
ansac ion audi ing, dispu e esolu ion, and egula o y
o e sigh . T anspa ency sa egua ds bo h use s and ins i u ions
by p o iding a e i iable ail o consen , logic, and execu ion.
Finally, in e ope abili y is he ounda ion ha enables agen ic
paymen s o unc ion globally. Agen s mus be able o ope a e
seamlessly ac oss paymen ails whe he ca d-based ne wo ks,
accoun - o-accoun ans e s, digi al walle s, o eme ging
decen alized sys ems. A p o ocol limi ed o one ne wo k o
ju isdic ion would only ep oduce he silos ha mode n
paymen sys ems a e ying o o e come. By emphasizing open
s anda ds, ex ensibili y, and c oss- ail compa ibili y, an agen ic
p o ocol like AP2 ensu es ha inno a ion can scale ac oss
ecosys ems.
The Agen Paymen s P o ocol (AP2) embodies each o hese
p inciples as co e design equi emen s. I p o ides he essen ial
p imi i e capabili ies, in en s, o e s, p oo s, and policies ha
In e na ional Jou nal o Eme ging T ends in Enginee ing and De elopmen Issue 15, Vol.6, 2025
A ailable online on h p://www. spublica ion.com/ije ed/ije ed_index.h m ISSN 2249-6149
DOI: 10.5281/zenodo.17682477
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make delega ion, nego ia ion, policy en o cemen ,
anspa ency, and in e ope abili y achie able in a epea able
and e i iable manne . AP2 does no me ely enable agen s o
pe o m ansac ions; i ede ines he language o us , consen ,
and execu ion in digi al paymen s.
V.
A
RCHITECTURE OF
AP2
The a chi ec u e o he Agen Paymen s P o ocol (AP2) is
designed as a laye ed amewo k ha ensu es cla i y o
unc ion, modula scalabili y, and secu e in e ope abili y. Each
laye in his a chi ec u e ul ills a dis inc ole, while oge he
hey o m a cohesi e and e i iable low om iden i y
es ablishmen o se lemen . This laye ed app oach allows AP2
o be lexible enough o di e se paymen ecosys ems while
main aining he obus ness and us equi ed o agen -d i en
inancial ansac ions.
Iden i y and T us Laye
A he ounda ion o AP2 lies he Iden i y and T us Laye ,
which es ablishes he undamen al us ela ionships be ween
all en i ies pa icipa ing in he ansac ion. E e y p incipal
whe he a consume , me chan , o ins i u ion owns iden i ie s
ha a e po able and e i iable ac oss di e en sys ems [5].
These iden i ie s can be ealized using decen alized iden i ie s
(DIDs) and e i iable c eden ials, allowing us o be
decen alized a he han dependen on any single au ho i y.
Agen s, ac ing on behal o p incipals, mus p o ide p oo s o
hei au ho iza ion o pe o m speci ic ac ions. These p oo s a e
ca ied as sho -li ed capabili y okens ha de ine he scope o
pe mi ed ac i i ies, alidi y pe iod, and e oca ion
mechanisms. The use o such ime-bound, c yp og aphically
e i iable capabili ies ensu es ha delega ion emains bo h
audi able and con ollable. Complemen ing his sys em a e us
egis ies, which main ain au ho i a i e lis ings o c eden ial
issue s, licensed au ho i ies, and sanc ioned en i ies. Th ough
hese egis ies, coun e pa ies can e i y c eden ial chains and
con i m ha all pa icipan s ope a e wi hin ecognized us
bounda ies.
In en and Scope Laye
The In en and Scope Laye cap u e he pu pose and limi s o a
paymen ac ion. This is whe e an agen ansla es a p incipal’s
needs in o a s uc u ed exp ession o in en . An in en ep esen s
wha he p incipal wishes o accomplish such as pu chasing a
p oduc o subsc ibing o a se ice and includes essen ial
pa ame e s like i em desc ip ions, quan i ies, desi ed p ices,
cons ain s, and use p e e ences. This in en ac s as a digi al
exp ession o pu pose.
Equally impo an is he de ini ion o scope. The p incipal
speci ies he bounda ies o an agen ’s au ho i y de ining limi s
such as pe missible spending anges, me chan ca ego ies,
app o ed coun e pa ies, ope a ional ime windows, and da a-
sha ing pe missions. These condi ions a e encapsula ed in a
digi ally signed capabili y documen , which se es as a
e i iable decla a ion o he agen ’s powe o ac ion. In some
cases, his capabili y may be co-signed by in e media ies like
ca d ne wo ks o walle p o ide s o ensu e en o ceabili y
ac oss ne wo ks. Toge he , in en and scope p o ide he
ounda ion o secu e and con ex ualized delega ion.
Nego ia ion and Policy Laye
The Nego ia ion and Policy Laye is whe e agen s in e ac
dynamically o align mu ual expec a ions and equi emen s.
When a paye agen publishes an in en , one o mo e me chan
agen s espond wi h s uc u ed o e s ha sa is y he s a ed
goals. Each o e may include de ails such as p icing, axes,
deli e y e ms, and applicable policy cons ain s [6]. This
in e ac i e exchange ans o ms paymen s in o p og ammable
nego ia ions a he han ixed-p ice ansac ions.
To go e n hese nego ia ions, AP2 in oduces a policy language
ha allows bo h pa ies o decla e logical condi ions ha mus
hold ue be o e a paymen can p oceed. Policies may include
know-you -cus ome (KYC) checks, sanc ions sc eening,
ansac ion eloci y con ols, geog aphic limi a ions, o age-
based es ic ions. The p o ocol employs a cons ain sol e ha
e alua es all applicable policies and compu es he se o
accep able o e s. When no o e sa is ies he policies in place,
he agen can ei he adjus i s pa ame e s o eques di ec inpu
om he p incipal, p ese ing bo h au onomy and o e sigh .
Au ho iza ion and P oo Laye
Once he paye agen selec s an accep able o e , he p ocess
ansi ions in o he Au ho iza ion and P oo Laye . This laye
ensu es ha all nego ia ed e ms a e secu ely bound o he
au ho iza ion e en , making he paymen bo h e i iable and
en o ceable. The paye agen compiles a se o claims co e ing
iden i y a ibu es, paymen ins umen e e ences, de ice o
en i onmen in eg i y, and p oo s o policy compliance and
p esen s hem o he payee o alida ion.
The me chan o payee agen e i ies hese claims and may
issue a challenge o con i m au hen ici y o in en . A success ul
e i ica ion p oduces a s able au ho iza ion eco d wi h a
In e na ional Jou nal o Eme ging T ends in Enginee ing and De elopmen Issue 15, Vol.6, 2025
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DOI: 10.5281/zenodo.17682477
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globally unique iden i ie . This eco d binds oge he he
ansac ion’s c i ical elemen ’s iden i y, scope, nego ia ed o e ,
policies, and p oo s ensu ing ha any change in condi ions
igge s a new au ho iza ion cycle. The close coupling o
au ho iza ion wi h nego ia ion p o ides a powe ul sa egua d
agains ampe ing o pos - ac manipula ion.
Se lemen and Repo ing Laye
The inal ope a ional laye in he AP2 a chi ec u e is he
Se lemen and Repo ing Laye , whe e inancial obliga ions
a e ul illed and eco ded. AP2 is agnos ic o he unde lying
paymen ail—i can ope a e seamlessly ac oss ca d ne wo ks,
accoun - o-accoun sys ems, and digi al walle s. Du ing
se lemen , emi ance de ails a e mapped o he ele an
ne wo k iden i ie s, such as okenized ca d e e ences,
me chan ca ego ies, clea ing codes, o emi ance IDs o
accoun -based paymen s.
E e y comple ed ansac ion gene a es a s uc u ed eceip
con aining de ailed line i ems, applicable axes, su cha ges, and
compliance a es a ions. These eceip s a e digi ally signed by
he me chan ’s agen , ensu ing hei in eg i y and enabling
o line e i ica ion. Addi ionally, eleme y s eams a e
gene a ed o p o ide eal- ime o ba ched insigh s in o
au ho iza ion e en s, p oo alida ions, and dispu e ou comes.
Impo an ly, all eleme y wi hin AP2 is designed o be p i acy-
p ese ing, ansmi ing only he minimal da a necessa y o
analysis o compliance moni o ing.
Co e Objec s and T ansac ion Flow
AP2’s ope a ion e ol es a ound a se o co e objec s ha
de ine he li ecycle o a paymen in e ac ion:
P incipal: The en i y—indi idual o o ganiza ion—
wi h legal and inancial s anding.
Agen : A so wa e sys em ac ing au onomously on
behal o a p incipal.
Capabili y: A c yp og aphically signed documen
g an ing an agen he igh o ac wi hin a de ined
scope.
In en : The s uc u ed exp ession o a goal o desi ed
ansac ion ou come.
O e : The me chan ’s s uc u ed esponse p oposing
e ms ha sa is y an in en .
Policy: The decla a i e ule se ha go e ns whe he a
ansac ion is pe missible.
P oo : A e i iable c yp og aphic s a emen
demons a ing ha policy equi emen s ha e been me .
Au ho iza ion: The binding eco d linking iden i y,
in en , o e , policy, and p oo o a paymen
ins umen .
Receip : The signed, immu able eco d summa izing
he inalized ansac ion.
The ypical AP2 ansac ion low p oceeds as ollows: he
p incipal i s g an s a capabili y o he paye agen , de ining
scope and au ho i y. The paye agen hen issues an in en o
exp ess a ansac ional goal. Me chan agen s espond wi h
co esponding o e s. The paye agen e alua es hese o e s
using he applicable policies, selec ing he one ha sa is ies all
equi emen s. The agen hen p esen s p oo s and ob ains
au ho iza ion om he payee. Upon success ul e i ica ion,
se lemen occu s h ough he chosen paymen ail, and eceip s,
along wi h p i acy-p ese ing eleme y, a e eco ded o bo h
pa icipan s.
This mul i-laye ed and objec -o ien ed a chi ec u e ensu es ha
AP2 deli e s secu i y, anspa ency, and in e ope abili y ac oss
di e se paymen sys ems. I no only accommoda es he cu en
needs o digi al comme ce bu also an icipa es he e olu ion o
agen -based economies, whe e so wa e-d i en nego ia ion and
consen o m he backbone o inancial us .
VI. I
MPLEMENTATION STRATEGIES
AP2 is a p o ocol. I can be implemen ed in s ages and wi h
exis ing in as uc u e.
Iden i y and capabili y
Use decen alized iden i ie s o po able iden i ie s.
Use e i iable c eden ials o a ibu es such as age,
esidency, and accoun owne ship.
Issue capabili y okens ha e e ence a e oca ion
egis y. Keep okens sho li ed and scoped o
ca ego ies and limi s.
Le e age secu e encla e signing keys on de ices and
ha dwa e secu i y modules in se ices.
T anspo
Use mu ual anspo laye secu i y be ween agen s.
Requi e o wa d sec ecy and ce i ica e pinning.
Use a message o ma ha suppo s canonical
se ializa ion and de ached signa u es. Concise bina y
objec ep esen a ion o JSON wi h clea
canonicaliza ion ules a e p ac ical choices.
In e na ional Jou nal o Eme ging T ends in Enginee ing and De elopmen Issue 15, Vol.6, 2025
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DOI: 10.5281/zenodo.17682477
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Suppo bo h synch onous and asynch onous
exchange so ha agen s can nego ia e e en when a
human p incipal is o line.
Policy and p oo
Adop a small decidable co e o he policy language
o ensu e ha e alua ion e mina es and is easy o
eason abou .
Use ze o knowledge p oo s o sensi i e a ibu es
such as age, esidency, o spending limi s. Re eal only
wha is needed o he speci ic policy.
Include de e minis ic audi logs ha link policy
s a emen s o p oo s and o he inal au ho iza ion.
Paymen ins umen s and ails
Fo ca ds, use ne wo k okens, dynamic ca d
e i ica ion alues, and isk signals om issue and
ne wo k. Bind au ho iza ion p oo s o ne wo k oken
me ada a.
Fo accoun o accoun , use scheme speci ic manda es
and signed consen a i ac s. Bind au ho iza ion p oo s
o he manda e iden i ie .
Fo walle s, use de ice bound keys wi h use p esence
signals o sensi i e scopes. Suppo aul ing whe e
he agen can hold a e e ence and no he aw
ins umen .
Risk and compliance
P o ide e e ence policies o common checks such as
wa chlis sc eening, eloci y limi s, and me chan
ca ego y es ic ions.
Allow a me chan o eques s onge p oo s when he
isk sco e is high.
Include s anda dized dispu e hooks so ha ei he side
can a ach e idence and s uc u ed explana ions.
De elope expe ience and go e nance
O e so wa e de elopmen ki s o common
languages, wi h s ong de aul s and clea gua d ails.
Main ain a con o mance es sui e and public e e ence
egis y o capabili ies o os e in e ope abili y.
Es ablish a go e nance model ha publishes e sioned
speci ica ions, egis e s ex ensions, and cu a es policy
empla es.
VII. H
OW
AP2
CAN TRANSFORM
PAYMENTS FOR CONSUMERS
AND MERCHANTS
Bene i s o consume s
1. Sa e delega ion. People can allow agen s o buy
household goods up o a budge , es ic pu chases o
amily accoun s, o block ce ain me chan ca ego ies.
The scope is explici and isible.
2. Be e p i acy. Agen s can p o e eligibili y wi hou
o e sha ing pe sonal da a. Receip s con ain only wha
is needed o a e sale se ices.
3. Sma e op imiza ion. Agen s can selec he bes
ins umen o he si ua ion, including ewa ds,
ins allmen op ions, o accoun o accoun o a oid
ees.
4. Fewe mis akes. Policy ca ches duplica e o de s,
unusual shipping add esses, o spending spikes be o e
money mo es.
5. Clea accoun abili y. E e y ac ion can be aced o an
agen and a capabili y ha ca ies consen .
Bene i s o me chan s
1. Highe con e sion. Agen s a i e wi h clea in en ,
s uc u ed o e s, and p ecompu ed p oo s o
eligibili y. Checkou becomes a con i ma ion e en
a he han a da a en y session.
2. Lowe aud and ewe cha gebacks. Policies and
p oo s mo e isk e alua ion ea lie in he low.
Dispu e e idence is s uc u ed and signed.
3. Riche o de da a. Line-i em eceip s and policy
a es a ions enable econcilia ion, wa an y se ice,
and egula o y epo ing.
4. Flexible se lemen . The same au ho iza ion eco d can
se le h ough ca ds, accoun o accoun schemes, o
walle s.
5. New expe iences. Me chan s can publish machine
eadable ca alogs and p omo ions ha agen s can
disco e and compa e.
VIII. F
UTURE DIRECTIONS
AP2 is a ounda ion. Many a eas dese e u he esea ch and
s anda diza ion.
In e na ional Jou nal o Eme ging T ends in Enginee ing and De elopmen Issue 15, Vol.6, 2025
A ailable online on h p://www. spublica ion.com/ije ed/ije ed_index.h m ISSN 2249-6149
DOI: 10.5281/zenodo.17682477
O iginal A icle
@2025 RS Publicaon, spublica[email p o ec ed]m
75
1. Human in he loop design. How and when should a
p incipal be p omp ed, and wha explana ions a e mos
e ec i e.
2. Mul i agen ma ke s. P o ocols o auc ions, bundles,
and dynamic p icing whe e many agen s nego ia e a
once.
3. C oss bo de compliance. Ha monizing policy
modules o di e en ju isdic ions wi hou
agmen ing he co e.
4. P i acy p ese ing eleme y. Me hods o lea n om
agg ega e ou comes wi hou exposing indi idual
beha io .
5. Fo mal e i ica ion. P oo s ha implemen a ions
p ese e he secu i y p ope ies o he p o ocol.
6. Sa e y guidelines o agen beha io o p e en da k
pa e ns and con lic s o in e es .
7. In eg a ion wi h iden i y walle s and sma eceip s
ha can be sha ed wi h accoun an s, employe s, o
insu e s.
IX. Conclusion
Agen s a e becoming a p ac ical way o na iga e comme ce.
They need a p o ocol ha ea s delega ion, nego ia ion, policy,
and se lemen as i s class concep s. AP2 p oposes such a
p o ocol. By sepa a ing conce ns ac oss laye s and insis ing on
e i iable p oo s and anspa ency, AP2 enables sa e au onomy
o e e yday paymen s. The esul is be e ou comes o
consume s and me chan s and a cleane pa h o egula o s and
ne wo ks o supe ise he sys em. The pa h o adop ion can be
inc emen al and can euse many elemen s ha paymen
ecosys ems al eady unde s and.
X. Re e ences
[1] ISO 20022 Financial se ices message s anda d.
[2] W3C Decen alized Iden i ie s and Ve i iable
C eden ials.
[3] FIDO2 and Web Au hen ica ion om he FIDO
Alliance and W3C.
[4] OAu h 2 amily o s anda ds and he la es guidance
on oken bes p ac ices.
[5] Ze o knowledge p oo sys ems and p ac ical p o ocols
such as Bulle p oo s and Plonk.
[6] Ne wo k okeniza ion speci ica ions om global ca d
ne wo ks.
[7] Da a p o ec ion guidance such as he Gene al Da a
P o ec ion Regula ion and he Cali o nia Consume
P i acy Ac .
