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

Annotations already declare readOnlyHint=false, idempotentHint=false and openWorldHint=true; the description goes beyond them by disclosing the mutation chain (a fork is published and parent-linked) and, valuably, that each call consumes one backtest credit. It stops short of stating explicitly that repeated calls create separate forks, which is the practical consequence of non-idempotency.

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?

A single dense sentence front-loads the verb chain and parenthetical only where it earns space (the merge example). No filler, no restatement of the title.

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 non-idempotent mutation with a nested-object parameter and no output schema, the description covers the workflow and cost but says nothing about the result — what identifier the new fork returns or how to reference it afterward — nor what happens on slug mismatch or validation failure.

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 only 25% — only as_of is documented — and the description compensates for exactly one parameter, explaining `changes` as a nested-merge patch with a concrete example. `slug` and `title` remain unexplained in both schema and description, so an agent must infer that slug is the source strategy identifier and title the fork's name.

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 description gives a precise verb chain (copies, applies changes, re-runs, publishes) on a named resource (a published Hub strategy), and the parent-link detail makes it clearly distinct from publish_strategy or run_backtest. An agent can predict the side effects from the first clause alone.

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?

Usage is implied by the operation sequence — this is the tool for deriving a new strategy from an existing published one — but no alternative is named (e.g. why not get_strategy + register_strategy + publish_strategy, or run_backtest for a trial run). The 'Costs one backtest' note gives useful cost context but not a when/when-not decision rule.

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