lob_list_self_mailersList sent/scheduled self-mailers, newest first. Lob API: GET /v1/self_mailers.
| Name | Required | Description | Default |
|---|---|---|---|
| after | No | Cursor for the next page (from a previous response's next_url). | |
| limit | No | Max results per page (1–100). Default 10. | |
| before | No | Cursor for the previous page (from a previous response's previous_url). |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already provide readOnlyHint=true, indicating a safe read operation. Description adds ordering detail ('newest first') and API endpoint reference, but no further behavioral traits like pagination behavior or data freshness are disclosed.
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?
Description is extremely concise: one sentence of purpose plus the API endpoint. No unnecessary words, front-loaded with core action.
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?
Lacks output schema explanation and does not describe pagination behavior beyond default ordering. However, the API endpoint reference and schema cover key details. Adequate but leaves some context for the agent to infer.
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 100% (all 3 parameters documented in schema). Description does not add any extra meaning beyond what the schema provides, meeting baseline expectations.
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?
Description clearly states verb 'List' and resource 'self-mailers' with ordering 'newest first'. Distinguishes from sibling tools for other Lob resources (postcards, letters, etc.) by specifying 'self-mailers'.
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 implies usage for listing sent or scheduled self-mailers but does not explicitly state when not to use or recommend alternatives. Scope is clear from the resource type, so it is easy to determine when to use.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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Every tool targets a distinct resource and action, with clear verb-noun names like create_address and verify_us_address. There is no overlapping functionality, and even similar operations (e.g., list for different resources) are distinct.
All tools share the 'lob_' prefix and follow a consistent verb_noun pattern (e.g., create_postcard, list_letters, verify_intl_address). Multi-word nouns use underscores, maintaining uniformity throughout.
With 18 tools, the set covers the primary mail fulfillment operations—address management, postcards, letters, checks, self-mailers, and address verification—without feeling bloated or sparse. The count is well-suited to the domain.
The tool set has notable gaps: no create_check or create_self_mailer, no cancel for letters or checks despite being referenced, no update/delete for addresses, and only list for templates. These missing operations will likely cause agent failures in common workflows.