Create an application user

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full load and does disclose key behavior: it mutates a live environment, requires confirm:true, otherwise performs a dry run, and runs the underlying 'pac admin create-service-principal' with the active auth profile. It omits permissions required and whether the operation is reversible, but the confirm/dry-run/mutation disclosure is substantive.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

It is front-loaded with the core purpose, but the confirm requirement is stated twice in near-identical form ('Changes a live environment: requires confirm: true' and 'Mutates a live environment: requires confirm: true (a dry run otherwise)'). This redundancy wastes space and the dry-run fact also duplicates the confirm parameter's schema description.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with no annotations and no output schema, the description covers mutation, confirm gating, dry-run behavior, and the underlying command. It does not indicate what the tool returns (e.g., application id, client secret), which an agent invoking a create tool would benefit from knowing given the absence of an output schema.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all 8 parameters thoroughly. The description reinforces the security-role and confirm-gating concepts, but adds little syntax or format detail beyond what the schema provides. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description gives a specific verb and resource: 'Register an Entra application and give it an application user with a security role in an environment,' and adds the purpose ('the headless identity a pipeline signs in as'). This distinguishes it in spirit from cs_admin_register_application, but it never names that sibling explicitly, so the differentiation is inferential rather than stated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The 'headless identity a pipeline signs in as' framing implies the use case (pipeline/service authentication), which is useful context. However, there is no explicit when-to-use vs alternatives guidance and no mention of the closely related cs_admin_register_application or cs_admin_list_service_principals, leaving the agent to infer the boundary.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.