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

Annotations declare destructiveHint=true, readOnlyHint=false and openWorldHint=false; the description goes beyond that with dedupe semantics ('recording the same insight twice replaces your earlier note; a pinned note is left as it is'), the fact that it is free, the required 'act' scope, and what the call returns. Only the exact irreversibility of an overwritten unpinned note is left slightly implicit.

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?

Well front-loaded: purpose first, then WHEN, then exclusions, then mechanics and return value. Some clauses are motivational rather than operational ('Recording it is part of the job, not a favour'), which costs a little density but does reinforce the tool's importance.

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?

There is no output schema, and the description compensates by describing the response ('their top moves with move ids, so recording hands you your next instruction without a second call'). With three params, dedupe behavior, scope, and cost all covered, an agent has everything needed to call this correctly.

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 meaning of kind, insight, and source_move_id is already fully documented in structured data. The description mostly restates those constraints (one sentence in the founder's own terms, 10 to 500 characters) without adding new format or syntax guidance, so a 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 plus resource ('write one durable thing you have learned ... into AfterLaunch's Memory') and explains the consequence of the write (drafts are written from Memory). It also routes the reader away from a near-sibling by noting that an approved writing rule belongs in record_voice_rule rather than here.

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 WHEN clause ('the moment the founder tells you something that will still be true next month and that AfterLaunch could not have measured itself') plus a concrete negative list: never record chatter, a passing mood, a restatement of the Snapshot or Memory, or anything inferred rather than heard. Alternatives (record_voice_rule) and the cost/scope prerequisite are named too.

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