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

Annotations only cover the generic mutation profile (readOnlyHint=false, idempotentHint=false, destructiveHint=false). The description adds high-value behavior the annotations cannot: this tool sends email to an external party, requires organisation-owner privileges, requires a write-enabled connection, and should be confirmed with the user first. It also states the return value ('the saved schedule with the date it first goes'), which is absent from annotations and there is no output schema.

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 purpose is front-loaded and each subsequent sentence carries a real constraint (permissions, connection scope, confirmation, sourcing, return value) rather than filler. It runs slightly long at six sentences for a description whose schema already covers most field-level detail, but nothing is redundant.

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 16-parameter mutation tool with no output schema and no field-level gaps in the schema, the description covers the non-schema essentials: authorization level, connection permission requirement, prerequisite lookups, the external-email side effect, and the shape of the response. An agent has what it needs to call this correctly or to decline.

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; the description still adds the non-obvious constraint that recipient and cc contacts each need an email address, and ties report_key/recipient/cc back to their source list tools. It does not add anything about the timing parameters (day_of_week, day_of_month, send_time, one-off dates), which remain schema-only.

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?

The opening sentence gives a specific verb and resource — it creates a recurring or one-off emailed report schedule — which an agent can act on immediately. It does not explicitly distinguish itself from the sibling update_scheduled_report or send_scheduled_report_now, so the create-vs-modify-vs-send boundary must be inferred.

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?

Explicit prerequisites are stated: only an organisation owner can see or set up schedules, the connection must be permitted to add/change records in that organisation, and the recipient/cc contacts must each have an email address. It also names the upstream tools (list_scheduled_report_types, list_contacts, list_organisations) that must be called first, plus a human-confirmation step before sending mail outside the app.

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