update_template_from_file

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

Annotations already declare destructiveHint=true and idempotentHint=true, so the description's job is to add context — and it does: the body is replaced wholesale, input must be UTF-8, and the call fails if LISTMONK_MCP_FILES_DIR is unset or the path escapes it. That sandbox/precondition detail is real value beyond the annotations. It does not discuss what happens to unspecified fields or the response, but the delegation to update_template covers that reasonably.

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?

Three short sentences, leading with what it does, then the sibling equivalence, then the failure conditions. Nothing repeats the schema and no sentence is 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?

For a destructive mutation with full schema coverage and annotations carrying the safety profile, the description supplies the preconditions and input-format constraints an agent needs to call it successfully. The only gap is how non-body fields are handled when omitted, which is pushed onto update_template rather than stated here.

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 coverage is 100%, so every parameter including file_path's 'inside LISTMONK_MCP_FILES_DIR (absolute or relative)' wording is already documented. The description only adds the UTF-8 encoding constraint and the directory restriction, which is marginal on top of the schema. 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?

Names a specific verb and resource (update a template) plus the exact mechanism that separates it from the sibling create/update tools: the HTML body comes from a UTF-8 file in LISTMONK_MCP_FILES_DIR. The phrase 'Otherwise identical to update_template' explicitly positions it relative to the closest sibling, so an agent can distinguish them 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?

The file-based mechanism implicitly tells the agent when to pick this over update_template, and the sibling is named for comparison. It also states the failure preconditions (env var unset, path outside the directory). It stops short of an explicit 'use update_template instead when you have inline HTML', so it is clear but not fully prescriptive.

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