template

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

Beyond readOnlyHint/openWorldHint annotations, the description states "Changes nothing", discloses that unknown refs produce an error, and explains which placeholders are auto-filled (recipient_name, recipient_first_name, my_name) versus manual. These are genuine behavioral additions rather than restatements of the annotations.

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, front-loaded with what is returned, then behavior, then errors. The placeholder/draft guidance is arguably more relevant to the draft tool, but it is compact and earns its place by clarifying follow-up usage.

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, the description need not detail return structure, and it still names the key fields, the error case, and placeholder semantics. Complete for a single-parameter read tool whose annotations already convey the safety profile.

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% and the single `ref` parameter is already documented in the schema as "the template's number or name, from templates". The description repeats that meaning without adding syntax or format detail, so the baseline of 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?

Specific verb ("Show") plus resource ("one saved template") and scope ("by its number or name"), and it enumerates the returned fields (To, Subject, text, placeholders). The parenthetical "(from templates)" implicitly distinguishes it from the sibling templates tool that enumerates them.

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?

It tells the agent to supply a number or name "from templates", implying the sibling lookup that precedes it, and explains how placeholders feed into draft ("pass the manual ones to draft as placeholder=['name=value']"). There is no explicit when-not-to-use statement, but the routing context is clear.

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