Borrowing it
Nothing to install: this file belongs to PedroMosquera/squadai. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/PedroMosquera/squadai/main/.agents/skills/sdd-spec/SKILL.mdgit clone --depth 1 https://github.com/PedroMosquera/squadaiWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/pedromosquera/squadai/sdd-spec)<a href="https://agentmods.dev/skills/pedromosquera/squadai/sdd-spec"><img src="https://agentmods.dev/badge/skills/pedromosquera/squadai/sdd-spec/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/pedromosquera/squadai/sdd-spec"><img src="https://agentmods.dev/badge/skills/pedromosquera/squadai/sdd-spec.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00013 | $0.00630 |
| Opus 5.5 | $0.00005 | $0.00252 |
| Sonnet 5.5 | $0.00003 | $0.00126 |
| Haiku 4.5 | $0.00001 | $0.00063 |
Grade A, and why
sdd-spec scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 16d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
SDD Spec Skill
Write a formal specification document that the Designer and Implementer will use as their source of truth. The spec must be complete enough that two different developers could implement the same behavior independently.
Steps
-
State the problem: Define what problem is being solved.
- What user need or system requirement motivates this change?
- What is currently broken or missing?
- What is out of scope (explicit exclusions)?
-
Define success criteria: List measurable acceptance tests.
- Each criterion must be testable (observable and verifiable)
- Use "Given/When/Then" or precondition/action/postcondition format
- Cover both functional and non-functional criteria
-
Specify the interface contract: Define the public surface precisely.
- Function/method signatures with parameter and return types
- Error types and when they are returned
- Side effects (files created, state changed, events emitted)
- Invariants that must hold before and after each operation
-
Specify data structures: Define all types involved.
- Fields, types, and optionality
- Validation rules (allowed values, format constraints)
- Serialization format (JSON schema, protobuf, etc.)
-
Specify behavior for edge cases: Cover boundary conditions explicitly.
- What happens with empty input?
- What happens with maximum-size input?
- What happens if a dependency is unavailable?
- What partial failure behavior is acceptable?
-
Specify non-functional requirements: Add constraints beyond behavior.
- Performance: maximum latency, throughput, memory usage
- Security: authentication, authorization, input sanitization
- Reliability: retry behavior, timeout, fallback
Output Format
## Specification: <feature name>
### Problem Statement
<1-3 sentences describing what problem this solves>
### Scope
**In scope**: <what this spec covers>
**Out of scope**: <explicit exclusions>
### Success Criteria
1. Given <precondition>, when <action>, then <expected outcome>
2. ...
### Interface Contract
#### <FunctionName>(params) (returnType, error)
- **Purpose**: <what it does>
- **Parameters**: <name type: description>
- **Returns**: <description of return value>
- **Errors**: <error type: when it is returned>
- **Side effects**: <what changes as a result>
- **Invariants**: <what must be true before/after>
### Data Structures
#### <TypeName>
| Field | Type | Required | Description |
|-------|------|----------|-------------|
### Edge Case Behavior
| Condition | Expected Behavior |
|-----------|------------------|
### Non-Functional Requirements
- **Performance**: <requirement>
- **Security**: <requirement>
- **Reliability**: <requirement>
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 16d ago Changed 0f1b3f6f28fe
- 1mo ago First seen · 87 lines · 13 tokens per session scan A d217d6d050b2
sdd-spec is a skill published in the GitHub repository PedroMosquera/squadai (10 stars, last pushed 4d ago), licensed MIT. It adds 13 tokens to every session and 630 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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