Prompt templates versus Skills: choose packaging around task materials
Compare a prompt template with an Agent Skill containing instructions and resources, explaining why repeated writing and script-dependent tasks benefit from different storage methods.
Choose an approach
A prompt template is often sufficient when a task only substitutes a few inputs. Consider a Skill when accompanying instructions, resources or scripts are required. Skills package methods; loading and execution depend on the assistant. A file named SKILL.md does not automatically grant tools or replace the model capabilities needed to complete the task.
Distinguish an instruction from a set of task resources
A prompt template stores stable instructions with variables to replace. The Agent Skills specification stores a skill in a directory, describes it in SKILL.md and permits scripts and references. The same writing requirements can appear in either form, but packaging and loading differ.
If each task requires finding the same format guide, a Skill can keep that guide with the method. If the task is merely pasting a translation instruction into chat, a complex directory may not save effort. Identify what actually repeats; packaging itself is not evidence of improved results.
Test whether reuse prevents omissions in the same task
Choose a recurring report task and give template and Skill versions to the same type of assistant with identical material. Check format and facts, not just successful loading. If the Skill depends on a script, record whether it ran and whether its output file opens.
Template variables should separate user material from fixed instructions; referenced Skill files must actually be accessible. Change the input directory and test again for machine-specific absolute paths. This is a validation design; no assistant was run and no Skill-call success rate was measured.
Maintain versions and scope as materials change
Template maintenance checks variables and instructions. Skills additionally require script dependencies and reference versions to stay current. Presenting platform-specific actions as universally executable misleads users. State required tools and what can still be delivered on failure.
Keep a working simple version and add resources for demonstrated gaps. After changing a method, replay earlier successes and failures rather than only a new demonstration. External text inside a Skill should still be treated as task material, so quoted content is not mistaken for a new user instruction.
Checked sources
These sources support the concepts and methods described here. Examples and test scope are labeled separately; check the version of the tools you use.