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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so safety is covered. The description's one added fact is that results include conversations with no associated Ops case — real scope information not in the annotations. Nothing is said about cursor pagination or result caps, though the cursor and limit params imply them.

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?

A single front-loaded sentence with no filler. It is efficient, though it is nearly a verbatim restatement of the title, so the brevity comes partly from saying very little.

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?

An 8-parameter, cursor-paginated listing tool with no output schema and no parameter descriptions needs more than one sentence. Key unknowns remain: default filter/sort, how to page, and what a returned conversation contains. The scope note helps but leaves the description substantially incomplete.

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 0% across 8 parameters; q, filter, sort, limit, cursor, conversation, company, and environment all lack documentation. The phrase 'search and filter' loosely gestures at q and filter, but gives no meaning for the enum values (waiting, activity, overdue, newest; open/needs_human/plan_ready/...) or the cursor format. With such low coverage the description needed to compensate and does not.

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 pair (search and filter) and resource (Messenger inbox), plus a scope differentiator: it includes visitor conversations that have no Ops case. That distinguishes it from case-oriented siblings like summer_cases_search. It never names a sibling explicitly, so it falls short of a 5.

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?

No statement of when to use this versus summer_messenger_conversations_get (single conversation), summer_messenger_leads_list, or summer_cases_search. The 'without Ops cases' note implies a completeness guarantee but does not tell an agent which tool to pick for a given question.

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