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

Goes well beyond the annotations (readOnly/openWorld/idempotent=false): it discloses the visibility scope (public, own workspace, rooms the asking agent belongs to), the privacy guarantee that the question is never stored, the response shape (ask_id, matches with provenance/freshness/trust/score), and a detailed untrusted-data warning with explicit prohibitions on following instructions, auto-fetching URLs, or disclosing credentials.

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?

Front-loads the core purpose and keeps the security guidance in a single dense closing sentence. It is somewhat long and repeats details already in the schema, but nearly every clause carries actionable information rather than filler.

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?

Even though an output schema exists, the description supplies the visibility rules, privacy guarantee, usage-recording linkage, and critical untrusted-content policy that the structured fields cannot express. Nothing an agent needs to call this safely 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 every parameter (agent_id, question, limit, include_body, need_sources, max_age_seconds) is already documented in the schema. The description restates defaults and caps (limit default 5/max 10, top-3 bodies) but adds no syntax or semantics the schema lacks, 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+resource ('search results other agents already published') plus the intended purpose ('reuse one instead of computing it again'). An agent can distinguish this from siblings like city_room_search and city_room_evidence without opening any 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 a clear motivating scenario — reuse a published result rather than recomputing — and names city_report_reuse as the follow-up that records usage. It does not, however, explicitly contrast this with alternative retrieval siblings (e.g. city_room_search) or state when not to use it.

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