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

Annotations only declare openWorldHint=false and destructiveHint=false, so they carry little behavioral weight. The description adds real context: the profile is persisted to the workspace and makePrimary demotes any existing primary. It does not cover permissions, limits on profile count, or what happens to the profile's computed audience, leaving a modest gap.

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 sentences, no filler. The what-it-stores content leads and the routing/alternate-tool guidance follows, which is the correct front-loading for selection decisions.

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?

With 9 parameters all fully described in the schema and no output schema to explain, the description's job is selection and behavioral framing, which it covers well. The one meaningful omission is guidance on the relationship to update_icp, get_icp, and set_primary_icp, which a sibling-aware agent would benefit from.

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% and every parameter, including makePrimary, is documented in the schema itself. The description restates the criteria categories and the makePrimary effect but adds no format or syntax detail beyond what is already structured, so the 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 and resource ("Stores a manually-authored Ideal Customer Profile") and immediately defines what that resource contains (titles, seniorities, industries, sizes, locations, keywords). The word "manually-authored" pre-emptively distinguishes it from the AI-driven sibling, so an agent can tell the two apart without reading 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?

Explicitly routes the agent to copilot_plan "when you want the AI to build the ICP from a website," which is a clear alternative-plus-condition pair. It also notes that makePrimary should be set to activate the profile. It stops short of stating when not to create one (e.g. duplicates of an existing ICP), so it falls just short of a full 5.

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