• an entity who is capable of action
• someone (or something) who acts on behalf of another person.

In law

• Agent (law): a person authorised to act on behalf of another person
• Patent agent, or patent attorney, a professional who represents and advises another in the assessment, securing and maintaining of intellectual property rights, with particular reference to patent rights.
• Tuition agent, a person who represents a tuition agency in searching for suitable tutors for students.
• Literary agent, a person who represents a writer
• Theatrical agent
• Booking agent
• Sports agent, a professional who represents an athlete
• Talent agent, a person who finds jobs for actors, models, and other people in various entertainment businesses.
• Press agent, publicist who acts on behalf of a client on all matters involving public relations
• Foreign agent, someone registered with the U.S. Justice Department as mandated by the Foreign Agents Registration Act
• Travel agent, makes vacation and travel arrangements
• Real estate broker, or real estate agent
• Yacht broker, or yacht agent
• Yacht charter broker, or yacht charter agent

In espionage and law enforcement

• Secret agent, a spy
• Double agent, in spying
• Special agent, generally, a federal criminal or non-criminal investigator or detective.
• Agent provocateur, a person assigned to provoke unrest, violence, debate, or argument by or within a group while acting as a member of the group but covertly representing the interests of another

In economics

• Agent (economics)
• Homo economicus
• Rational agent
• Agent-Based Computational Economics
• Representative agent

In chemistry and warfare:

• Agent Orange, a herbicide
• Biological agent, an infectious disease that can be used in biological warfare
• Chemical warfare agent, classified by their effect and include:
• Nerve agent
• Blister agent
• Blood agent
• Pulmonary agent
• Incapacitating agent
• Riot control agent.

In linguistics

• Agent (grammar), one of the thematic roles: the participant of a situation that carries out an action. Replaces "subject" in placement typology.
• Agent noun (or nomen agentis), one of the derivatemes (a topic from linguistic morphology)

In computer science

• Software agent, software that acts on behalf of a user
• Forté Agent, a newsreader and email client
• User agent, a client application used with a particular network protocol
• Intelligent agent
• In artificial intelligence an intelligent agent is any entity that is capable of perceiving its environment and carrying out goal-directed action (also sometimes called a rational agent).
• In computer science, an intelligent agent is a software agent that displays some intelligence.

In fiction

• Agent 212, a Belgian comic
• Agents, characters in The Matrix
• The Agent (film), a 1922 film
• Secret Agent (1936 film), a 1936 film
• The Agents, superhuman characters in Seven Samurai 20XX
• Agent 47, a character from the computer game series Hitman
• Agents, rouge killers from the novel T.O.M. tom

In finance

• Agent, a financial institution acting as the operational intermediary in a syndicated loan between the syndicate banks and the borrower. The most common form is the "Administrative Agent".

In popular culture

• Polish version of The Mole.

Others

• Election agent, a person responsible for a candidate's campaign
• Free agent, a sports player who is out of contract
• Rational agent deliberate being

See also

• Agent architecture
• Agent based model
• Robot
• bot
• personoid