Create Federation Rule

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

Goes well beyond the annotations by naming the security consequence (the rule grants access and permits authentication), the exact return payload and its fields, and concrete authorization constraints: org admin, user session or OAuth with full_access, and an explicit exclusion for API keys and workload tokens. That exclusion is precisely the kind of failure mode an agent cannot derive from readOnlyHint/destructiveHint/idempotentHint.

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?

Four short sentences ordered by importance: what it does, its effect, what it returns, then who may call it. No filler and no repetition of schema constraints.

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?

Auth requirements and return shape are covered well and the absence of an output schema is mitigated by the explicit return description. However, for a 13-parameter privileged-creation tool with a nested claim_conditions object, the description gives no guidance on how to obtain an issuer_id or principal_id, or what claim_conditions keys are valid, leaving required-parameter construction under-specified.

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 only 23% across 13 parameters (10 required), and the description supplies almost nothing to compensate. The phrase about mapping an external identity loosely gestures at issuer_id/claim_conditions/principal_type, but claim_conditions structure, allowed_audiences, database_roles, permission, name pattern, and the non-inherited database default are all left undocumented.

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?

States a specific verb and resource ("Create a cluster rule") plus the core effect ("mapping an external identity to your user or a service account"), which is far more informative than the title. It stops short of explicitly contrasting itself with update-federation-rule or create-federation-issuer, so an agent must infer the boundary from the name alone.

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?

Usage is implied by "An enabled rule permits authentication and grants the configured access," which hints this is the setup step before token exchange works. There is no explicit when-to-use/when-not guidance and no pointer to update-federation-rule for modifying an existing rule, so routing between the federation CRUD siblings is left to inference.

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