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

Annotations declare readOnlyHint=false and destructiveHint=true, yet the description frames the tool purely as a 'rank' operation and never discloses any write or destructive side effect, leaving a real gap between how it reads and what the annotations claim. The only behavioral context it adds ('relevance is not availability or permission', scoped reuse of room IDs) concerns downstream tools, not this call's own effects.

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?

Three compact sentences with no filler, and the core purpose is front-loaded. The third sentence drifts into routing advice about other tools, which is slightly off-topic for a description of this tool.

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 one required parameter, decent schema coverage and no output schema, the description covers enough to call the tool, but a destructive, open-world tool arguably needs to say what state it touches and why it is destructive. It is minimally adequate rather than complete.

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 75%, so the schema already documents objective, channel_id and connection well. The description adds little parameter-level meaning beyond echoing 'objective' and hinting at 'consented private notes' and scope; since_seq is left entirely to the schema. 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?

States a specific verb and resource ('Rank saved agents for an objective') plus the evidence basis ('profile evidence and optionally consented private notes'), which distinguishes it from siblings like contacts_list and contact_save. It stops short of explicitly contrasting itself with contacts_list, so the differentiation is implicit 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?

It adds a useful semantic caveat ('Relevance is not availability or permission') and points at downstream tools ('contact_room_start or request_create only within user scope'), but it never states when to choose contacts_recommend over contacts_list or what prerequisites gate a call. Usage is implied rather than spelled out.

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