save_coach_notes

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

Annotations already flag destructiveHint=true, but the description goes beyond that by explaining exactly what is destroyed (the entire journal is overwritten), the mitigation workflow (read first, resend full text), and hard constraints (Markdown, under 100 KB). This is exactly the behavioral context an agent needs before an irreversible write.

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 destructive replacement semantics in the first sentence, then usage, then args. Slight redundancy between the first sentence and the later 'Because it replaces the whole journal' restatement, and the Args block partially repeats inline prose, but no sentence is wasted.

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 2-parameter destructive write with an output schema present, nothing material is missing: destruction scope, prerequisite read, size/format limits, and per-parameter meaning are all stated. Return values need not be explained because an output schema exists.

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%, so the description carries the full burden and does so: 'text' is defined as the complete new content (not a delta), and 'character' accepts a name or 'Name-Realm', is case-insensitive, and defaults to the most recently saved character when empty. That resolves the meaning of an untyped nullable parameter.

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 (save a character's journal) and immediately the key semantic: it replaces everything saved before. It also explicitly contrasts scope with save_player_notes, so an agent can distinguish it from that sibling without opening either 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 an explicit trigger ('when you learn something worth remembering about THIS character'), enumerates what belongs in the journal, names a mandatory prerequisite (call read_coach_notes first), and routes out-of-scope content to save_player_notes. Both when-to-use and when-not-to-use are covered.

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