set_account_slot

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

No annotations are provided, so the description must carry the burden. It usefully discloses that 'Values are stored as strings' and describes the key-value pair storage model, plus the account reference formats (full path, %short GUID, 32-char GUID). However, it doesn't specify whether setting an existing key overwrites it, whether there's a size limit, or whether this requires specific permissions. For a write/mutation operation, this is useful but incomplete behavioral disclosure.

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 description is well-structured with a one-line summary, then a context paragraph, then an Args section. It's concise without wasted words. The only slight inefficiency is the docstring-style 'Args:' section format, but all content is informative and earns its place.

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?

The tool has 3 params, no annotations, and an output schema exists. The description covers param semantics thoroughly and gives usage context for a write operation. While it could disclose overwrite behavior and permission requirements, the description is largely complete for this straightforward metadata-set operation given the available schema context.

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 0%, so the description must compensate for parameter documentation. It does this well: 'account' gets explicit format examples (full path, %short GUID, full GUID), 'key' gets example values ('apr', 'credit_limit'), and 'value' notes it's always stored as a string. This adds real meaning beyond the bare schema which only defines types.

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?

Clearly states it 'Set a custom metadata slot on an account' with specific verb+resource. Distinguishes from siblings like get_account_slots and delete_account_slot by the action (set vs get/delete) and gives concrete use cases (APR, credit limits, reward rates). The purpose is unambiguous.

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 description explains it's for 'per-account metadata' and lists example use cases, providing clear context on when to use. However, it doesn't explicitly contrast with siblings or state when NOT to use it. The sibling tools get_account_slots and delete_account_slot imply the complementary operations, but no explicit guidance is given.

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