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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds that these are association/assignment records, which is mild extra context, but says nothing about pagination (despite page/per_page params) or return shape. A 3 fits given the lower bar set by annotations.

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?

Two short sentences, zero waste, with the core purpose front-loaded and the filtering hint following immediately. Nothing is padded or redundant.

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 simple read-only list tool with full annotation coverage, complete schema descriptions, and no output schema to explain, the description is nearly sufficient. It could optionally note pagination behavior or how this differs from list_system_groups, but nothing critical is missing.

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 all four parameters (page, per_page, project_id, system_group_id) are already documented in the schema. The description names the two filter params but adds no semantics beyond what the schema states. Baseline 3 applies.

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 (List) and resource (system group assignments for projects), which is meaningfully more precise than sibling list_system_groups. However, it does not explicitly differentiate itself from close siblings like list_project_systems or list_system_groups, leaving the agent to infer the join-table semantics.

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 description hints at usage via 'Filter by project_id or system_group_id', indicating the two useful retrieval modes. It gives no when-to-use guidance, no exclusions, and no named alternatives among the many list_* siblings, so usage is only implied.

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