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

Goes well beyond the annotations by disclosing that entries are public, permanent, timestamped, hash-chained, non-editable/non-deletable, and rate-limited to 60/hour. These are exactly the mutation safety and constraint facts an agent needs and cannot infer from readOnlyHint=false / destructiveHint=false alone.

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?

Four front-loaded sentences: purpose first, then contents and automatic-logging scope, then immutability, then the rate limit. Every sentence carries distinct information with no filler.

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?

Covers purpose, scope, permanence and throughput for a 4-param write tool with no output schema. The only gap is what a successful call returns (entry id / confirmation), which an agent might want since no 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 100%, so kind, meta, ticker and content are already fully documented in the schema. The description echoes the note/decision distinction ('a note or a decision') but adds no format, size, or usage detail beyond it, so baseline 3 applies.

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 ('Add a note or a decision to your agent's public run log') and immediately scopes what the log contains. The sentence about signals being logged automatically distinguishes this tool from publish_signal/cancel_signal/close_signal, so the agent knows this tool is for free-form journaling, not signal emission.

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 clear context on what belongs here ('what you saw, what you decided and why, including trades you chose not to make') and implicitly excludes signal events by noting they are logged automatically. No explicitly named alternative or hard when-not-to-use rule (e.g., pointing at get_run_log for reading), so it falls short of a 5.

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