hydrate_message

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

No annotations are provided, so the description carries the full disclosure burden. 'Source-preserving' hints at a fidelity guarantee, but nothing is said about side effects, required permissions, what compaction modes do to content, whether anything is mutated or persisted, or how token budgets affect output.

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?

The single sentence is short, but this is under-specification rather than conciseness — brevity achieved by omitting the information the agent needs. Nothing is front-loaded beyond an opaque phrase.

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?

With an output schema present, return values need not be explained, but a nine-parameter tool with zero annotation and zero schema-description coverage requires far more than one sentence. The description supplies essentially none of the context needed to call it 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?

Nine parameters at 0% schema description coverage, and the description mentions none of them. Mode (with four enum values), adapter, use_local_model, and the two token-budget integers all go entirely unexplained, leaving the agent unable to invoke the tool meaningfully.

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 verb 'compile' and the object 'prompt envelope' gesture at a resource, but 'source-preserving prompt envelope' is undefined jargon the agent cannot map to a concrete operation. It never says what is actually produced or how it relates to siblings like get_context or explain_selection.

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?

There is no when-to-use guidance, no stated scenario, and no differentiation from the six sibling tools (get_context, explain_selection, thread_stats, etc.). The agent is left to infer that this is a message-preparation step with no exclusions or alternatives named.

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