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

Annotations only give coarse flags (readOnlyHint=false, destructiveHint=false, openWorldHint=false). The description adds the behavior that actually matters: the run carries no payload, configuration is read live at dispatch, OwnerId is unconditionally OVERWRITTEN with no distinction between unowned and already-owned records, and a credential may request review but never release it. The overwrite disclosure slightly outpaces the coarse destructiveHint=false, but it refines rather than reverses the annotation.

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?

The tool description is three tight sentences with no waste: mechanism first, then the no-payload/config-at-dispatch constraint, then the overwrite warning and the scoping remedy. The safety-critical constraint (OVERWRITES) is capitalized and front-loaded where an agent will see it.

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 5-parameter mutation with no output schema, the definition covers nearly everything needed to invoke it correctly: required calls, scoping semantics, validation timing, and the destructive-write caveat. The one gap is that it never says what creation returns (a run id, a run object, or nothing), which an agent dispatching a follow-up may want.

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 baseline is 3, and much of the filter_spec wording duplicates the schema. The description still earns above baseline by explaining parameter absences (no assignment_spec, no mode, no strategy/field/pool, no write_back) and the validation timing (object_type and filter_spec validated at creation so bad input fails there rather than as a dispatch-time decline).

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 concrete verb+resource (create an assignment run) and then unpacks the actual mechanism — read a configured field, map its value to a rep pool, pick a rep by the pool's rotation, write OwnerId. It explicitly distinguishes itself from the nearest sibling ("NO assignment_spec, and that is the whole difference from a Mass Update run"), so an agent can route between create_assignment_run and create_mass_update_run without opening either schema.

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?

Gives explicit when-to-scope guidance ("scope with filter_spec if you mean only unowned records"), prerequisite calls (list_filterable_fields for field names/operators, list_crm_connections for a connection_id), and states what is deliberately NOT an input and why (no strategy/field/pool because that is per-tenant configuration read at dispatch; no write_back because the write is unconditional). Alternatives and exclusions are both named.

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