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

Annotations already declare destructiveHint=true, openWorldHint=true and readOnlyHint=false, so the description must add nuance — but it does not say whether this is a partial/PATCH-style update or a full replacement of warmup config, nor what a 'destructive' update can wipe out. It also omits whether warmup changes take effect immediately or reset sender health, which matters for a settings mutation with 28 fields.

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?

One sentence, front-loaded and easy to scan, but the opening clause 'Update Sender -' merely restates the name and title before any content, so a meaningful fraction of the text 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 28-parameter mutation with only 'id' required and an output schema present, the critical missing piece is update semantics: are omitted fields left untouched? Is 'folder' emptied differently than other fields? The annotations carry the safety profile and the schema carries field meaning, but the partial-update contract an agent needs before calling is absent.

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 one of the 28 parameters is already documented in the schema; the description only echoes a handful of field areas (warmup, inbox, signature, tracking domain). It adds no semantics such as how arrays like warmup_urls or warmup_templates replace existing values, or how the folder/workspace_id scoping interacts with the update.

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 (Update) and resource (email sender settings) and enumerates representative field areas — warmup, inbox, signature, tracking domain — which maps well to the largest parameter clusters in the schema. Sibling tools with similar nouns (get_all_senders, update_sequence, reconnect_sender) are implicitly distinguished by the verb, but the description never names them explicitly.

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 guidance on when to call this versus get_all_senders, get_sender_health, reconnect_sender, or update_workspace. There are no stated prerequisites (e.g. needing the sender id, permissions, or workspace scoping) and no exclusions or warnings despite destructiveHint being true.

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